Yoshiyuki Terada teaches at Tomoeda Elementary School, serving as the homeroom teacher for the main characters through fourth and fifth grade. He's also involved in other school duties—PE classes, field trips, the usual stuff.
The manga takes his character in a surprising direction: he's in a romantic relationship with his student Rika Sasaki. They get engaged when he gives her a ring with the hope it'll become her wedding ring someday. Rika makes him a teddy bear and names it after herself, claiming old legends say it'll keep them in love forever. Nobody else seems to know about them, though there's a telling moment late in the series where the couple's having a picnic in the park and Terada ducks away so Sakura won't spot him. When Rika gets possessed by the Sword card and Sakura uses the illusion ability to see what Rika loves most, she hears her call out "Sensei"—a detail that doesn't leave much to the imagination.
The anime handles this very differently. The engagement, the romantic moments—all gone. Instead, Rika just mentions that Terada reminds her of her absent father, which reframes the whole dynamic. He still accepts her homemade cakes and the bear, but he names it after his "hardest working student" rather than anything suggestive. The Cardcaptors English dub went even further, stripping away every trace of romance between them. Rika's shyness around him just becomes generalized anxiety around men instead of actual feelings.
Content compiled by AnimeList.moe from publicly available sources.
