Ryuusei Okada 岡田流星
The protagonist of this story. A normal high school student who has the privilege of having the 'girl with the largest breasts in the world' as his classmate. A breast lover, his one pleasure in his otherwise boring high school life is sneaking looks at Oki's breasts. Katagiri noticing this moves to block his view much to his chagrin. This begins the battle of wits between Okada's attempting to sneak glances at Oki's breasts as Katagiri prevents him from doing so.