go together
go together {v.}
1. To go with the same boy or girl all the time; date just one person.
Herbert and Thelma go together.
Compare:
GO WITH (2),
2. To be suitable or agreeable with each other; match.
Roast turkey and cranberries go together.
Ice cream and cake go together.
Green and yellow go together.
Categories:
Source: A Dictionary of American Idioms