I'm just broke's manga / #Old Turned Young(1)

Forgot to add this to my reading list. Oops. - - - Veteran spy or assassin gets hit by a radioactive wasp and doesnt turn into wasp man, he turns back into his younger self while on a mission. - - - When I first read, the story was treading on thin ice. I was highkey suspicious of the mc, since he is just a grown man in his younger self's body going to a middle school. But dw guys, hes not a weirdo, just dont get why the author had to make the characters say the strangest lines and then one page later its "Haha! This is not that type of Manga." Like you're the one giving me a heart attack, but youre also the one who suddenly had a change of heart and decided to give me a defibrillator?? EXCUSE ME? (Does that make sense?? lMFAO I RE-WORDED THIS SO MANY TIMES.)