Seungho is a mentally unstable person and probably because of his traumatic past. This isn't your normal fluffy manhwa. He doesn't know how to express his growing feelings in a correct way because he has mental illness. Nakyum isn't the only one suffering.
The first couple had a little problem at the start but at the end, it was consensual and the seme really considered the Uke and was gentle with him ♡♡