沢村たち青心寮5号室メンバーは、ひょんなことから猫を飼うことに。食事は？ お風呂は？ しかも寮はペット禁止!?次から次に襲い掛かる超難問に沢村たちは悪戦苦闘……。それでも彼らはくじけない。だって猫のかわいさを知ってしまったから！猫と球児の日常を描く、『ダイヤのA』ほっこりスピンオフコメディ。

A warm comedy spinoff series from Ace of the Diamond (aka Daiya no A) written by Yuki Okada, the wife of Yuji Terajima himself.

Sawamura and his fellow residents of room 5… accidentally adopted a cat? What will they do about meals? How will they bathe him? Worst of all, pets are prohibited from being kept in the dorms. Sawamura and his roommates struggle to overcome these challenges while keeping their new feline friend a secret. Still, they persevere, because who can resist the cuteness of cats?

Read Daiya no C to follow the adventures of the Seidou team and their new furry addition.