Yeah, the joke is that candy "お菓子" can be pronounced the same as "fucked" "犯し". So, Yuubari took Samidare's request for candy or a trick will be played "that" way.
More commit a sexual crime (primarily rape) than just 'fuck', but yes. There's also that 悪戯, in addition to being the benign 'trick' is also rape/molest/sexual misconduct.
So basically it's "If you don't rape me, I'm gonna rape you!"
Well... I mean, if she's asking for it, maybe I'll just straight up give her that sweet lovin' now... But just a moment... If I don't give it to her she'll "get me" right? Maybe I should let her get me first, then give her the sweet stuff afterwards?... 'That' sweet stuff...? Like sweet loving? Or she'll get me?Take this...And come get me!Gimme that sweet stuff, or else I'm gonna getcha!