Karaa Ni Kuchizuke summary:

Miki Kuroda, a college student, was forced to wear a collar in the past and has come to reject Doms due to his trauma. However, his body continues to seek for more, and he deals with the overflowing heat by reading erotic novels.One day, when working as a babysitter, Miki meets Moriya, a Dom. Despite being confused, he manages to finish his work, but happens to go into heat.  Moreover, when he finds an erotic novel, Moriya notices his lower half-!A sensual novelist (dom) x a traumatic college student (sub). A dom-sub universe that is sweet and gentle enough to sprout in a world where there is a master-slave relationship.