彼は自らの強欲に負けてしまった。

he; him; his; boyfriend

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

for one's self; personally

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

greed; avarice

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

to lose; to be defeated; to succumb; to give in; to surrender; to yield; to be inferior to; to break out in a rash due to (e.g. lacquer, shaving, etc.); to reduce the price; to lower the price; to give a discount on