貝合わせ: tribadism

勝平: a male given name

開幕: rising of the curtain of a stage, the beginning of a performance; opening of a ceremony, festivity or conference

to buy so as to gather

(literary, uncommon) to argue

(slang) Alternative form of かっこいい

river surface

(video games) to provoke hatred from other players

maple / Liquidambar formosana, Chinese sweetgum tree, Formosan sweetgum tree

(rare, zoology) a sea lion / (rare, zoology) a seal