The U20 Squad (Striders, Fukuhara, and Jaime Flowers) VS fanmail:
(AKA the Boxes sequel that I will never write)
Chrono got some Chronojet merch, clocks, and way too many cinnamon buns. He also got cute letters and swirly lollipops from kids because his fights were really cool and apparently he’s everyone's hero now, and... oh huh, are kids trying to copy his hairstyle?
Taiyou got a lot of random sun-themed decorations, a hoodie with a lion mane trim, and a ton of plushies. Also, he received a significant number of letter and gifts from older girls who found him "cute like a teddy bear".
Kazuma didn't understand what the point of all this was. He didn't think the letters and gifts were cool until he opened up a custom-made, hyper-realistic replica of Luard's arm that he could wear as a glove.
Shion got the regular amount of (read: too many) fangirl letters, chocolates, and flowers. Apparently, a lot of said fangirls were going to try and get into Fukuhara for high school because they wanted to "Vanguard with Shion-kun~!" Surprisingly, he also got some not-as-cringy letters from kids and other fighters who were fired up from his fight with Chrono.
Hayao didn't expect to have any fans. His fans showered him with praise about his fight with Verno. Hayao vowed to write thank-you letters to each and every fan, while Shion tried to convince him that that was physically impossible to do.
Rin knew that she obviously had many fans. And honestly, she didn't care about what they were sending her. (Of course, that doesn't mean that she won't read all their letters when she gets home later. Also, she's secretly hoping that there were a few packages of gourmet lollipops somewhere in that pile.)
Tokoha got a lot of flowers. Like, enough to fill half of Card Capital 2. About half said flowers were sent by Jaime. Besides that, she got some flowery accessories, fun fanart, and a few letters from her friends in France.
Kumi received encouraging letters, plushies, and many, many crosses. Also, Jaime gave her the same amount of flowers as he gave Tokoha.
Satoru didn't think that he deserved fans. He received a (to him) surprising amount of congratulations for his fight against Onimaru Kazumi and - even more shockingly - love confessions. He did not understand why the world was being so kind to him. He decided to try harder in order to be worthy of such forgiveness.