noun
rice weevil
Literal meaning: a small insect that infests stored rice. The word is also used figuratively for a person who lives off others.
米びつに米食い虫がわいてしまった。
Rice weevils have infested the rice bin.
noun
good-for-nothing; parasite; deadbeat
Derogatory term for a person who is useless, lives off others, or contributes nothing. Often used in insults.
あいつは働きもせずに親の金で暮らしている米食い虫だ。
That guy is a deadbeat who lives off his parents' money without working.