Is Sekaiichi Hatsukoi: Valentine-hen hentai?
No
Rated PG-13 (Teens 13 or older) on MyAnimeList and not tagged as Hentai.

Movie · 2014 · 1 episodes · PG-13 - Teens 13 or older
Adult Cast, Boys Love, Workplace
Animated short with an original story that was screened alongside "Sekaiichi Hatsukoi Movie: Yokozawa Takafumi no Baai."
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