The couple holding hands (Nitoko and Kotoni's older brother and best friend) were, originally, gonna be two girls. ^^' I changed my mind at the last second.
Ariwashi (the blue-haired boy) is making fun of the panel by slumping his shoulders. YOU MEANIE!
For those confused...
In Japan, PDA is a social crime. Nitoko and Kotoni both hate PDA.