"Happy Birthday, Shumai!"
Kokichi hands Shuichi a present box decorated in purple with an indigo ribbon. Upon opening it, it turns out not to be a normal gift box.
No, the present box is a Jack-in-the-Box with the ribbon acting as the crank. The moment it's tugged, a jester that looks suspiciously like a certain, familiar purple clown jumps out of the box and springs to the tune of "Pop Goes the Weasel."
After Kokichi has a good laugh at Shuichi's reaction, he pulls out a second present, a large detective novel tied in a sparkly purple ribbon that thankfully doesn't have anything dubious about it.
"Oh...! For me?" Well that was a nice surprise: Kokichi seemingly handing Shuichi a normal looking gift with nothing else up his sleeve! At least... that's what he thought.... "Thank you, Ouma-ku-"
...Until he was about to unwrap it, only to yelp when he, instead, pulled the crank that makes the jester in the box pop out! "Waauughh!!!"
He nearly dropped the box with how much it was stumbling around in his hands with how hard he jumped. And looks just like that mischievous gremlin, too, because of course it does!!! "O-Oh my god..." A hand to his chest, he just exhales as he hears that boy laugh. "Y-Yep, I should have known that you had something up your sleeve, you...!!!"
A harmless swat is given to Kokichi's arm with a corner of the box. He wasn't mad, of course, since even he can admit he got him pretty good! And he'll laugh it off at the end of the day... Though what catches him by even greater surprise is that Kokichi really did have a gift for him in the end.
"! Y-You really had something for me, after all?" A detective novel... a huge one at that!! Oh he was immediately invested, taking the gift in his hand as he undoes the ribbon. "This book...! I've been meaning to get this for a while! How'd you know!" He was excited to read it, already!! This boy... really is full of surprises. But without a doubt, he made Shuichi very happy. Though he won't let him get away with being the only one who gets teased here, and so, as Shuichi steps closer, he... puts a hand in Kokichi's hair and starts to wildly ruffle it.
"Payback." He smirks. The boy's hair was usually wild looking, anyway, so he won't mind, right? Then with a laugh, his expression softens as he says: "...Thank you, Ouma-kun. You gave me a good laugh and a nice gift!"