Bromion is a character in the mythology of William Blake. According to S. Foster Damon (A Blake Dictionary) he represents Reason, from the side of the poet's mind.
In Vala, or the Four Zoas he is one of a quartet of four sons, with Rintrah, Palamabron, and Theotormon, whose parents are Los and Enitharmon (or alternatively, sons of Jerusalem).
He is a major character in Visions of the Daughters of Albion. He rapes Oothoon, and then is bound to her, back to back.