Japanese by Example
Learning through examples in manga

Coming to buy coffee mugs with 〜に来る

ご注文はうさぎですか? » Volume 1 » Page 53

Rize explains that she (along with Chino and Cocoa) came to buy cups to use in the coffee shop.

リゼ:
喫茶店(きっさてん)使(つか)うカップ()いに()んだよ」