(Somehow I lined this up yesterday but utterly forgot to actually post it on schedule. My deepest apologies for any inconvenience!)
Literally: uncontrolled / licentious – oppress – violence – revert
Alternately: Crude, lecherous, boorish, cruel, violent, and lacking any empathy or mercy – in look, behavior, lifestyle, and/or general condition.
Notes: This is a relatively obscure and literary phrase, and my computer’s IME doesn’t even offer the character 婬 as an option when I type いん! (Incidentally, this character may be replaced with its more accessible cousin 淫 without any change in meaning or pronunciation. That said, the latter does seem to be significantly less common in terms of this yojijukugo.)
This is another compound of compounds. 婬虐 is “cruel and improper [behavior]”; 暴戻 is “brutality,” “tyranny.”