No, Agent 99 dresses him in boxers, and he mutters about how he prefers briefs because they give him more support.
Also (SPOILER ALERT):
He changes clothes between when 99 dresses him and when his pants get ripped.
Whatever causes his pants to rip wouldn't realistically leave his underwear intact. Actually, it wouldn't leave his skin intact, either, but he's uninjured for comedic value. |