(Internet slang) Abbreviation of ブルーバック.

play dumb, feign ignorance / (slang) evade one's responsibilities, especially by failing to appear to perform a duty

(colloquial) current boyfriend

everything

(slang) Alternative form of 彼氏 (kareshi, “boyfriend”)

everyone, one and all

Alternative form of ファストバック (fasutobakku, “fastback”)

(American football, Canadian football) a quarterback

Alternative form of クォーターバック (kwōtābakku, “quarterback”)

(Internet) trackback