1x28 - Beelzebub

The students of Ishiyama High are ordered to do physical examinations amongst themselves. Baby Beel gets jealous of a toy which accidentally gets stuck to Oga's back, and locks himself inside of a locker to pout in protest. While trying to lure him out, the girls come into the room for their physicals, forcing Oga and Furuichi to hide under the desk while the girls strip off and start measuring. The girls leave the room without seeing them, despite a few close calls, and upon the girls' departure Oga and Furuichi get up from under the table and start trying to lure Baby Beel out once more. Aoi returns to the classroom moments after leaving, and finds the two of them in the room. She realizes that they have been there all along, and goes on the offensive. During the conflict Baby Beel exits the classroom through an open window and climbs into Sadohara's sports car, and locks the door behind him, which Oga is unable to pull open. Baby Beel "springs a leak", filling the car. Oga, unable to think of any other option, chops the car resulting in the entire shell of the car shattering.