Fly Me to the Moon, Vol. 11

During their camping trip, the gang surprises Nasa and Tsukasa with a belated wedding reception and a glampsite with a king-size bed! When they're not blushing and stammering their way through the festivities, the no-longer-newlyweds consider what marriage means to them. Maybe it's time to move out of the neighborhood bathhouse and into a place with a little more privacy.

Volume 11 of the Fly Me to the Moon manga series by Kenjiro Hata.