My answer did not provide enough information. Can you provide more information about this person, such as his character name, which work he appeared in, which historical period, etc.? This way, I can better help you answer your questions.
It was rare for the female lead in anime to have a human body and a snake tail, but it was not unheard of. Some anime works might create a female protagonist with a special body structure, such as a human body and a snake tail. This setting was usually used as a plot setting or character feature to make the female protagonist more unique, interesting, and able to attract the audience's attention. However, whether it appeared often or not depended on the specific work.
Your request is a little vague. I'm not sure what kind of novel you want. If you can provide more details and background information, I will be more than happy to help you.
The situation of anime characters transmigrating to another anime did not exist in real life, but it might happen in some novels and comics. For example, in some novels or comics, the protagonist might travel to another world in some way and become another character there. This situation was usually used to enhance the storyline of a novel or manga and to provide more background and experience for the characters. However, this plot was not a real situation in the real world. It was just a fictional plot.
I recommend the novel " Reborn as a Snake: I Can Simulate Life Unlimited " to you. Although the title looked a little strange, the plot of this sci-fi novel about evolution and mutation was very interesting. The protagonist, Ling Jiu, transmigrated to a parallel world with the recuperation of reiki and became a young Black-scaled Snake. He obtained a life simulator. He devoured the flood dragon, suppressed the Human Martial Saint, and destroyed the Divine Throne. Billions of gods trembled under his fierce might! I believe you will like this novel too. I hope you will like this fairy's recommendation.π
In Japanese anime, there are many characters with human bodies and snake tails, some of which are very famous. For example, Naruto's Uzumaki Naruto was a character with a human body and a snake tail. His tail beast mode was composed of snake tail attacks. In addition, Monchi D. Luffy in One Piece also had the image of a human with a snake tail. His rubber fruit ability allowed him to turn his body into rubber and have the special attack of a snake tail. In addition, Fliesa in Dragon Ball was also a character with a human body and a snake tail. He was a demon with strong combat power.
The person could have thrilling moments, like going on quests or dealing with supernatural threats together with the snake girlfriend. There might also be tender and romantic scenes that showcase their deep bond despite the differences.
It could be seen that "Under One Man Season 2" was an existing animation. According to the search results, the anime had 24 or 25 episodes, with a rating of 9.0 or 0.0. The main plot of the anime revolved around the world of mutants. In order to unravel the secrets of his grandfather and himself, the protagonist Zhang Chulan participated in the grand event of the mutant world, the Heavenly Grand Ritual, and fought with many mutant masters. However, the specific way to watch the anime and the platform information were not found in the search results provided. Therefore, he could not answer the question of watching the anime accurately.