sharing a room (accommodation)

mutual, reciprocal, with one another / appearance, look

nature, personality / fate, destiny / a habit, custom, or practice / the good and bad of a person; especially, one's faults

minister of state

appearance, how something looks / an aspect of something / (grammar) grammatical aspect / (physics) a phase, as of matter / (ikebana) the central supporting branch of an ikebana arrangement

黒い: black

畔, 畦, 壠, 壚, 夔, 奝: a low dike separating two rice paddies; a low rise, a small hill / 黒: black

黑川, 黒川: a surname

黒貂: (zoology) sable

黒長蟻: Messor aciculatus, a species of black ants found in East Asia and Russia