"President Rias Gremory's virginity belongs to me!"
— Issei Hyodo, setting the stage.
"Remember to practice with these."
— Xenovia offering Issei some condoms...in the middle of homeroom.
"My name is Rias Gremory. And I am a Devil."
— Rias Gremory presenting herself to Issei.
"I want you to remember him. The man called Issei Hyodo."
— Ddraig, after Issei's death and his conversation with Ophis.
"I won't forget. My only friend."
"If it's a god then I will kill it with this spear. Come, let the battle begin."
— Cao Cao
"I just believe in my own body, that's all."
— Sairaorg Bael
"I, who shall awaken, am the Heavenly Dragon who stole the principle of "Domination" from God."
"No, I'm the Red Dragon Emperor who said fuck the principle of "Domination"."
"I laugh at the infinite and fret over the dream."
"I got infinite hopes and dreams suckers, and imma be badass!"
"I shall become the Red Dragon of "Domination"."
"F that shiz, more like I'll become the Red Dragon King!"
"I shall drown you in the depths of crimson Purgatory!"
"I promise everyone! I'll show you a future that shines of deep crimson!"
"Future?! You think you can show us?!"
"Yeah son! Chill, I've got this! Or, ya know what? We'll show 'em together! Our comrades, the women we love, and the children!"
"We can show them!"
"Let's go you old geezers! I'm the Red Dragon Emperor! And the Grabbin Dragon! The man in love with Rias Gremory! I am Issei Hyoudou!"
— Issei, rejecting the former Boosted Gear users desire to use the Juggernaut Drive and instead convincing them to awaken the Cardinal Crimson Queen.
"Would you sell your soul to the devil? No? How about if theyre stonkingly hot and have a batallion of attractive followers? Yes? Well, here you go; youll like this show!"
— MasakoX, recapping the series.