Is Kun Tun Tianxia Zhi Zhang Men Guilai hentai?
English title: The All-devouring Whale: Homecoming
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

ONA · 2025 · 12 episodes · PG-13 - Teens 13 or older
Action, Fantasy
Fan Lingxiao, a gifted spirit pet master, was ambushed in the A-level sect promotion competition and devoured by his own spirit pet whale, Kun. When he woke up, he found himself reincarnated into a young man named "Liu Fengmang" who is imprisoned in the White Mansion. His sect, Lingxiao Pavilion, was also in dire straits. In order to find out the truth about the backlash of the spirit Kun and revive his sect, Fan Lingxiao takes his existing spirit pets and embarks on a new adventure with Gu Ling, Cheng Xi, and Yue Tong. (Source: Bilibili, translated)
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