WARNING: the following contains spoilers for Episode 1 of TONIKAWA: Over the Moon For You, now streaming on Crunchyroll.
In the new anime TONIKAWA: Over the Moon For You, the protagonist is Nasa Yuzaki, but the real driving force of the story is the mysterious girl known as Tsukasa, who might not even be mortal. In this new rom-com anime's debut episode, Tsukasa appears and disappears at will, wandering off into the moonlit night or appearing again when it suits her. She reminds Nasa of the Japanese folk tale of Princess Kaguya, who had to return to her home in the heavens. Perhaps Tsukasa has a similar deal.
Tsukasa's Offer to Nasa
The inciting event of this new animated series is a traffic accident: a young man getting hit by a truck. In an isekai anime, this cliche would lead to him being reincarnated in another world, but Nasa is spared, all thanks to Tsukasa. Nasa survived because Tsukasa threw herself between Nasa and the truck, and once Nasa was back on his feet, Tsukasa took a liking to him, and vice versa. Nasa was smitten by this gorgeous, mysterious red-headed girl in the moonlight, and the two of them hit it off. Tsukasa seemed a bit reserved about it, but then she made the offer of a lifetime: marriage.
Tsukasa liked the idea of being Nasa's friend, but she wanted to put the cart before the horse and marry him, then let their relationship take root. It was totally backwards, but Tsukasa was barely even fazed by the bizarre nature of this deal. With practically no hesitation, Nasa accepted Tsukasa's offer, then fainted from blood loss. By the time Nasa awoke in the hospital, months had passed, and his moonlit fiancee was gone, just like that. He wouldn't see her again for a few years.
Tsukasa Is Not What She Seems To Be
When Nasa is 18, he gets a surprise visit from Tsukasa at night, once again under the full moon. It seems Tsukasa only appears when that moon is high in the sky, and even at the end of this episode, Tsukasa is walking off into the moon backdrop, as though going home. Why does she appear and disappear according to the full moon? She seems rather active late at night, and she has yet to appear in the daylight hours. If this keeps up, it may strongly suggest that something supernatural is going on.
It's odd Tsukasa suffered so few injuries after throwing herself between Nasa and a truck. She was also slow to give her own name, and Nasa didn't learn it until they met again a few years later. Even then, Nasa didn't learn Tsukasa's last name (Tsukuyomi) until he saw it on the marriage license papers. Now, Tsukasa's going to take Nasa's last name to become Tsukasa Yuzaki. Why is she so quick to hide and get rid of her last name?
Tsukasa is acting a bit like a magical girl, an unusual young lady appearing in the ordinary male lead's life and totally turning it upside down. She hasn't used magic or stepped into a UFO just yet, but the story's tone suggests mystery and the supernatural. She is rather like the mythical Princess Kaguya, and so far, the possibility of her being a reincarnation of that goddess can't be ruled out. The mystery deepens.