Bocchi OL Nano ni, Naze ka Shanai No.1 ni Amaama ni Saretemasu!?

Sumiko Yamadera is a kind-hearted female office worker who is considered strict by everyone around her, but in reality she is just a woman of few words. In order to make her wish come true, she first applies for a rental boyfriend to get used to being with a man, only to have the company's top salesman come to her door!

(from mangaupdates)