mudskipper of the species Boleophthalmus pectinirostris

王殺し: regicide

裘, 皮衣: fur coat

煮頃鮒: nigorobuna (Carassius auratus grandoculis), a type of 鮒 (funa, “crucian carp”), an edible freshwater ray-finned fish related to carp and goldfish, endemic to Lake Biwa in Japan

見頃: best time to see / 身頃, 裑: body of a garment

国五郎: a male given name

standing by and watching as someone dies, without offering help / (figuratively) to neglect a person having difficult circumstances and not assist him or her

Alternative spelling of 人殺し

killing of parent(s)

murder / murderer