(anglicism) regret (remorse) / (decision theory) regret

叩き込む: dive into, throw into, hammer in, beat in

海: sea / 膿: pus, suppuration / 生み: birth; stem form of 生む

alternative spelling of 蟷螂 (kamakiri, “mantis, insect of the family Mantidae”) / alternative spelling of 杜父魚 (kamakiri, “fourspine sculpin, a freshwater fish”)