Mayonaka no Orphée

In his childhood, insomniac Kazushi was plagued with terrible nightmares. But when he hears the low and gentle voice of his colleague Wabuka, he's lured into drowsiness... so much so that he faints. Knowing that Kazushi is able to fall into a deep sleep when he's with him, Wabuka suddenly blurts out, "Shall we live together?!" To Isshi, two men in their thirties living together and sleeping belly to belly is unthinkably strange, but Wabuka is rapidly becoming very precious to him.

(Source: Libre, translated)