Dragon Ball fans are once again using May 9 as an excuse to show their love for the series' iconic hero, Son Goku.

May 9 has become an unofficial holiday for fans of Akira Toriyama's genre-defying anime and manga series, as the date 5/9 can be read in Japanese as "go" (five) and "kyuu" (nine), which almost sounds like the beloved martial artist's name when read together. Fans across the world got both "Goku" and "Goku Day" trending on various social media networks as they shared their favorite moments with the character, fan art, and inspirational messages in the spirit of the optimistic, limit-pushing fighter.

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In addition to highlighting their favorite moments and images of the character, many discussed how Dragon Ball introduced them to the world of anime and manga and reflected the impact the series has had on not just those mediums, but on video games, movies and comics from around the world. While the day is focused on Goku, many fans also thanked artist Akira Toriyama for creating the character.

Son Goku was introduced to the world in the first chapter of Toriyama's Dragon Ball manga, which was first published in the pages of Weekly Shonen Jump way back in 1984. After crash landing on Earth, the initially ultra-aggressive infant Goku is raised by Gohan, a kind, elderly martial artist, in the woods. Gifted with immense strength and a natural talent for the martial arts, Goku begins to explore the world after meeting his first friend, Bulma, and agreeing to help her find the wish-granting Dragon Balls. The series then follows the young martial artist through countless battles and stages of life, including his tutelage under the perverse martial arts expert Master Roshi, his marriage to Chi-Chi, the birth of his children, and his multiple deaths throughout the second half of the series.

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Dragon Ball is the third best-selling manga series of all time, with over 260 million copies in circulation worldwide. The series' animated adaptations, specifically Dragon Ball Z, are credited with helping to establish anime's worldwide popularity in the late 1990s and early '00s. Goku's adventures continue to this day with the on-going Dragon Ball Super manga, which is still overseen by Toriyama and features art by his protegé, Toyotarou. The franchise will release its newest movie, entitled Dragon Ball Super: Super Hero, in Japan on June 11, with a North American release planned to follow sometime shortly afterwards.