Rookie band BOB4 displayed their close friendship with BtoB through a recent photo.

On September 21st, leader Sung Yoo Bin and drummer Hwang In Hweh of BOB4 updated their Twitter accounts with the photo above and wrote, "We're the B brothers. Kekeke. We always use the same waiting room at 'Music Bank'."

The two groups can be seen posing closely together and displaying their friendship in the photograph. Although both groups pursue different style of music, BOB4 and BtoB seem to have built a close relationship as their group names share the similar initial.

Source: Hwang In Hweh's Twitter