They're the text book goofy goobers, every single one of them xD Absolutely no way this little stunt doesn't end with embarassment and police being called in. Maybe paisen is going to actually go to jail, since he bought the items and made the bombs. I know it's more like "everything is batshit crazy" type of manga, but we saw with the teacher not too long ago - when it gets real, it gets real.
Gotta say, Tobio is my boy, truly. He wants to get back for his homie straight away, has a chance to fumble both the plan and Renko, but instead fumbles none (so far) - that's some potential. I don't think she was all sincere though. For some reason I trusted Isami's GF from the 1st chapter more, despite her being a "stereotypical gyaru".