"You can be both my friend and my lover."
Ao and Kaya have been childhood friends since middle school.
Ao was small and cute, someone Kaya could talk to about anything without thinking of him as a guy.
Even now, with his height approaching 190cm, Ao was still Kaya's only male friend.
---Until just a moment ago.
(Source: Libre, translated)
— Description from AniList community (anilist.co).