Can we just talk about smol jellybean Matsus? What if s/o is joking with them & is like "Who said that?" Looks around all dramatic "Must've been the wind" finally they're like "oh! I didn't see ya down there!" before smoochin his cheeks...I'm so mean
omg that’s cute! （˶ ・⌄ ・˶ ）
I think Osomatsu would absolutely roll with it, giving you a playful “you little-!” while grinning like an idiot. He tackles you later when you’re not paying attention, demanding more kisses.
Since Karamatsu is used to being ignored, he would actually be happy you made a joke with him rather than using him as the punchline. He thinks that it would make a nice recurring gag and will try to convince you to form a duo with him in skits more frequently.
Choromatsu gets pissed easily, and he would most certainly go on one of his “you big people with your even bigger attitudes” rants. Sometimes he tries to kick you in the ankle, too, though it’s always just for show and he never uses enough force to actually hurt you - on the other hand, it makes him look even more ridiculous. He is easily pacified with kisses, so it’s okay.
Ichimatsu would give you the death glare, but that’s all. Expect him later to randomly pounce at you when you’re most vulnerable, though… Biting will be included.
Jyushimatsu would make the face, and after a few seconds of staying silent, he would just randomly pick you up and run around with you as fast as he can.
Totty would honestly just keep making a pouting face at you until you apologize. Beware, he is willing to ignore you for the rest of the day if you’re not fast enough…