Kitto Ouji-sama ga Nante
きっと王子様がなんて · きっと おうじさま が なんて
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
Sakura, who continues to live alone even after reaching the age of 30, decides to marry in order to reassure his parents. But the truth is… he’s an otomen who likes cute stuff and is a closet gay man. Keeping these circumstances hidden, he goes to a marriage counselor and reunites with his younger childhood friend Yuusuke by chance.
Source: AniList
External databases: MADB · AniList
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