Where does “bad boi” come from?

bad boi (English) comes from English boi, from Portuguese bumba-meu-boi, from Portuguese boi, from Old Portuguese boi, from Latin bovem, from Latin bos, from Ancient Greek βοῦς, from Latin corvus — army.

Ancestry of “bad boi”, step by step

bad boi traces back through two separate lines of ancestry.

via English boi

StepLanguageWordMeaning
1EnglishboiA male bottom (i.e. submissive partner), defined not by junior age, but by his obedient role and submission to the dominant "top"
2Portuguesebumba-meu-boi
3Portugueseboiox
4Old Portugueseboi
5Latinbovemaccusative singular of bōs; cow, bull
6Latinbosa cow, bull, or ox; cattle
7Ancient Greekβοῦςcow, ox, cattle; shield: ὃτι ἐκ βοείων ἐστι...
8LatincorvusA raven; a bird associated with prophecy and...
9Proto-Italickorwos
10Proto-Indo-Europeanḱorh₂wós
11Proto-Indo-Europeanḱer-to grow, to make grow, to nourish; to plait,...
12Proto-Indo-Europeankr̥-to turn, to bend
13Proto-Indo-Europeanker-army

via English bad boy

StepLanguageWordMeaning
1Englishbad boyUsed other than with a figurative or idiomatic...
Every word from Proto-Indo-European ker-Every word from Proto-Indo-European kr̥-Every word from Proto-Indo-European ḱer-