Thread:GamingEmpire/@comment-1471207-20170815212557/@comment-26500386-20170815220121

While that's true, he also specified that it was a "hint", meaning that there is no official explaination yet.

I do agree with you that it's probably the case that the Quirk was stolen from Bakugou's childhood friend, but until we get the confirmed information, it shouldn't be put on the Wiki as anything other than speculation.