@Raudhbjorn she's the wife. his harem is apparently every single female around him since they all are either interested in him or quickly fall to his charms if need be.
@AbyssalMonkey well, meili can be seen/read as Chinese(Mandarin). It is the romanization (Pinyin) for the word beautiful and various other words depending on how you pronounce it.
@AbyssalMonkey Meili is a nordic name, it's the name of one the Odin's kid
MC realy need to understant that he love the cute demon lord. It would make the story progress a lot, and i bet she would accept Milia as the 1st mistress.