SEE YOU LATER, MERMAID

After meeting in a seaside town during their solo-travels, Kazushi Kimijima and Tatsumi Higaki find themselves as patrons of the same inn. The friendly Kazushi invites the pensive Tatsumi for a drink as a favor for his help during a prior sand-in-eye plight. Kazushi finds out little by little why his new acquaintance is so apprehensive. What will he do when Tatsumi unveils his deepest secret and with it, his deepest fear? (Source: Futekiya) — Description from AniList community (anilist.co).