Mr Nice Guy
noun /ˌmɪstə ˈnaɪs ɡaɪ/
/ˌmɪstər ˈnaɪs ɡaɪ/
(informal)- a way of describing a man who is very honest and thinks about the wishes and feelings of other people
- I was tired of helping other people. From now on it was no more Mr Nice Guy (= I would stop being pleasant and kind).