noun
chubby girl; plump girl
Slang term, often used affectionately or in otaku/manga contexts to describe a girl with soft, squishy cheeks or a plump figure. Related to the mimetic word ぷにぷに (squishy).
See also: ぷにぷに
あのぷに子ちゃん、ほっぺたが柔らかそう。
That chubby girl looks like she has soft cheeks.
最近のアニメにはぷに子キャラがよく出てくる。
Chubby girl characters often appear in recent anime.
From the mimetic word ぷにぷに (squishy) + 子 (common suffix for female names or nicknames). The exact origin is uncertain, but it likely emerged in otaku or internet slang.