Goku isn't perfect, we all know this. He may protect the world from powerful threats, but he's not always the greatest in the personality department. The thing about the Dragon Ball series is that it's constantly shifting. Creator Akira Toriyama would rarely plan more than a few chapters ahead when writing the original manga and as a result, some things got forgotten both by Toriyama himself and fans of the franchise. Because of this, Goku's horrific deeds, shortcomings and personality flaws aren't addressed as much as they should be.

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Everyone's favorite Saiyan has a lot of dark secrets, ones that get buried under the rug and forgotten about. Some of these can be chalked up to his Saiyan heritage, others are a result of his naivety or general low intelligence. But, Goku isn't a terrible person, his heart is almost always in the right place, he just tends to screw up royally from time to time. There are a lot of terrible moments in the Dragon Ball franchise that are pretty much the direct result of Goku's actions. However, not everything dark about Goku is his fault, but that doesn't make things any better.

15 HE WAS SENT TO DESTROY EARTH

Goku is part of the Saiyan race, a powerful species enlisted by Frieza to conquer planets for his empire. Saiyans have natural instincts to fight and destroy, which is the reason why even the youngest Saiyans can take over planets by themselves. In fact, some Saiyans are sent to planets as babies to take them over using their great ape forms.

This was the reason that Goku was sent to Earth, to destroy the inhabitants and conquer it. However, after being found by his adoptive Grandpa, Gohan, he suffered a head injury, resulting in a change of personality. What should have been ruthless instinct was turned into good-heartedness by the head trauma. The people of Earth are lucky this happened, since Goku has saved them more times than they know.

14 HE KILLED HIS GRANDPA

The Great Ape transformation is what makes a Saiyan powerful enough to conquer planets as children, it is also somewhat unstable. When a Saiyan looks at a full moon, their eyes absorb an energy known as "blutz waves." These blutz waves combine with glands in their tail and transform them into giant ape monsters.

Vegeta was able to use an artificial source of blutz waves to voluntarily transform into a great ape, but Goku was victim to the lunar cycle of Earth's moon, transforming into a monster during a full moon. Because of this, Goku turned into a Great Ape during a full moon and killed his grandpa by stepping on him. The worst part is that Goku didn't realize he was the monster that killed Grandpa Gohan until Vegeta revealed that all Saiyans can turn into great apes.

13 HE CAN'T HOLD A JOB

If there's one thing that Dragon Ball fans know, it's that Goku isn't the greatest husband and father. Overall, he's actually very protective and caring towards his wife and sons, doing anything to protect them. However, with the little things, Goku tends to screw up. For example, he's not really good at holding down a job.

Goku often has to be forced by his wife to work the farm that provides their family's main income, usually finding ways to weasel out of it and train. We might not know much about farms, but just straight up abandoning them in the middle of the season usually means the crops go bad. Even when Chi-Chi and Mr. Satan set up a security job for Goku in Dragon Ball Super, something he could actually be good at, he gave up after about five minutes of wearing a suit and hair gel.

12 HE'S AFRAID OF NEEDLES

After facing some of the strongest enemies in his universe and others, one might assume that Goku is practically fearless. But, that assumption would be incorrect as Goku has one major fear: needles. It seems silly in retrospect, since he's fought powerful enemies and sustained horrific injuries, yet he makes a huge fuss about a tiny needle.

We saw this fear when Goku was in the hospital after fighting Vegeta. The doctors were trying to give him a shot, but he yelled and thrashed despite his injuries. His whining was so pathetic that Chi-Chi left her husband in the hospital, irritated and ashamed of his irrational phobia. This fear came up again when Vegeta was prepping Goku for the healing tank and he spotted a needle, causing him to make a mad dash for the exit.

11 HE'S ONLY KILLED TWO VILLAINS

Goku has a nasty habit of sparing his enemies, something that actually comes from his warrior code of sorts. He respects a good fight with a strong opponent, which is why he often makes friends with most of the enemies he has faced. Despite being the hero who defeats the bad guys once and for all, Goku has only ever killed two of his enemies over the course of Dragon Ball Z.

The only two villains that Goku ended in Z for good were Yakon and Kid Buu, both from the Buu saga. Yakon was a villain that devoured light energy, something he thought to be an advantage, but ended up being his downfall. By continuously powering up, Goku fed Yakon so much energy that he exploded. As for Kid Buu, we all know he used the spirit bomb to defeat the demonic villain.

10 HE'S NEVER ACTUALLY BEATEN VEGETA

Vegeta's most well-known trait is his Saiyan pride, and when it is wounded, it sparks a drive to get stronger. Specifically, he is always striving to surpass Goku, a Saiyan born to a low-class family that constantly breaks all of his limits. Despite the fact that Goku often reaches new heights before Vegeta, he has never actually defeated the prince of Saiyans.

In his first fight with Vegeta, Goku was close to dying at the hands of the Great Ape form, but was spared when Yajirobe cut off Vegeta's tail. Later, on Namek, Goku is defeated by Vegeta's superior fighting skill and power. Lastly, during the Majin Buu saga, when Vegeta becomes Majin Vegeta, he overpowers Goku, who admittedly was holding back Super Saiyan 3 at the time.

9 HE LEFT CHI-CHI ALONE AND PREGNANT

Goku has died twice in the series, and because of a rule with the dragon balls that is often ignored with other people, he could not be resurrected by the Dragon Balls after his death in the Cell saga. Speaking of the Cell saga, sometime before the Cell games, Goku and Chi-Chi spent some intimate time together, conceiving a second child. However, Goku didn't know about Goten at the time of his death, or even after.

Sure, Goku didn't know about his second child, thus making his "abandonment" less terrible, but he also didn't need to die. When Cell was going to blow himself up and destroy the world, Goku used instant transmission to bring him to King Kai's planet, sparing the lives of the people of Earth and dying in the process. However, couldn't he have just as easily transported back to Earth before the explosion to spare his life?

8 HE'S AN ACCIDENTAL PERVERT TO BULMA

The early days of Dragon Ball were a lot more comedy-driven, focusing on the fun adventures of a little monkey-tailed boy and a teenage girl searching for the legendary dragon balls. A lot of the comedy of the original series was derived from Bulma, specifically in the form of sexual humor. Goku, being the naive little kid that he was, often invaded Bulma's privacy in inappropriate ways.

When he first met Bulma, Goku lifted up her skirt, curious because he'd never seen a girl before. Later in the series, he would both touch her pelvic region and remove her underwear while she slept, completely oblivious to the implications of these actions. Recently in Dragon Ball Super, Goku developed ki sickness, which caused his instant transmission to malfunction, leading to him transporting in Bulma's room while she was half-naked.

7 HE'S NEVER KISSED HIS WIFE

In the Goku Black saga of Dragon Ball Super, Trunks gave Mai a senzu bean when she was passed out, chewing it before locking lips and feeding it to her. When he did this, Goku was surprised at the action, saying he'd never done that. Vegeta was shocked at this, bringing up the fact that Goku is married. But Goku had no idea what one had to do with the other, meaning that he has never kissed Chi-Chi.

We know he's not the greatest husband, but how has he never kissed his wife? He's had kids after all! Maybe he's done it but doesn't remember because of his less-than-stellar memory. Whatever the reasoning, we're surprised Chi-Chi hasn't threatened a kiss out of her husband, since that's how she usually gets things from him.

6 HE KILLED KING KAI

We mentioned that Goku gave his life to save the Earth in the Cell Saga. He saved the Earth by taking an about-to-explode Cell to King Kai's planet, far away in otherworld. This, of course, resulted in the deaths of King Kai, his monkey Bubbles and super speedy cricket, Gregory. While this act did save the Earth, it was still kind of a jerk move.

Sure, King Kai exists in otherworld already, so dying means he doesn't really go anywhere, and he seems to have retained his living body, but being dead is clearly bothersome to King Kai. Goku basically saw King Kai's life as expendable in his decision, which is probably why he was so mad and wants Goku to wish him back to life.

5 HE'S TURNED DOWN A TON OF MONEY

Since Goku isn't too great at working, be it on the farm or at a security job, and all he's concerned with is training and fighting, we can assume that he doesn't bring in that much cash to the Son household. In fact, he doesn't seemed concerned with money to begin with, which he should be, since he probably racks up a huge food bill.

Goku is so unconcerned with money that he turns it down in the first episode of Dragon Ball Super. When Goku was taking a break from farming, Mr. Satan showed up and offered him 100 million Zeni as a thanks for defeating Majin Buu, which the world thinks Mr. Satan did. It's a lot of money and Goku basically wants no part in it, not even knowing the worth of it. Fortunately, Goten convinces him to take it so he can stop working and train.

4 HE'S BROKEN THE RULES OF THE AFTERLIFE

When someone dies in the world of Dragon Ball, they can only be resurrected once by the dragon balls of a specific planet. After dying in the Cell saga, Goku could not came back to the world of the living again. The specifics of this rule aren't exactly clear, but for the sake of argument, Goku has broken the rules of the afterlife on multiple occasions.

Goku kept his physical body after his two deaths, since both times were heroic sacrifices. Most dead people do not get to keep their bodies, so already Goku gets special treatment in the afterlife. Later, Goku's 24-hour period amongst the living in the Buu Saga was shortened due to going Super Saiyan 3, but Babba Yagga still allowed him the time to say goodbye. Lastly, after defeating Kid Buu, Goku was granted life once again for his heroic acts, breaking the rules again.

3 HE BEATS UP HIS FRIENDS AND FAMILY A LOT

When Goku trains with his friends and family, he often spars to test their skill. This has, on more that one occasion, led to Goku straight up beating on his friends and sons. Goku fights Krillen, Gohan and Piccolo to test the results of their training a few times in both Dragon Ball Z and Dragon Ball Super. 

But, this isn't the only reason he beats on his friends. After he got back from space, he accidentally patted Chi-Chi on the back so hard she flew through the side of their house. This happened because he wasn't used to Earth's gravity, and thus didn't know his own strength. He also punched Gohan to stop him from going after Cell, saying it was for his own good.

2 HE'S RESPONSIBLE FOR THE TOURNAMENT OF POWER

Goku is a martial artist through and through. He loves a good fight and respects the fighting ability of others, even the most evil of his opponents. Goku is constantly looking for strong enemies to fight, often putting himself and others at risk to find a good fight. This desire of his is what led to the tournament of power, a battle royal between eight different universes.

But, this isn't just a fight for the fun of it, it is actually a competition to see which universe will survive being erased. See, because of their low rate of intelligent life, these eight universes are set to be erased, but the two Zen-Ohs will spare whichever one can win the tournament of power. It is because of Goku's casual friendliness with Zen-Oh that the king of everything used his suggestion of holding a fighting competition to decide which Universe will survive.

1 HIS BODY WAS USED TO KILL

Prior to the universal survival saga, there was the Goku Black saga. Goku Black was the result of Supreme Kai Zamasu trading bodies with Goku in order to destroy all mortals. Zamasu used the super dragon balls to change bodies with Goku, and in his body he began to kill every human in sight. This includes all of Goku's friends and family.

Yes, you read that right, a god used Goku's body to kill all of Goku's loved ones. Think about how dark and horrifying that is. Goku's oldest friend, Bulma was killed at his hands. His wife and sons were murdered by the face of the man that has protected them for years. Even Goku himself, in Zamasu's body, looked into his own eyes as he died. Now that's some dark s***.

Can you think of any other dark secrets about Goku? Let us know in the comments!