Fairy Leviathan belonged to the 4 guardians who defended humanity, you were part of the resistance against Neo Arcadia, You fought to make the leader of Neo Arcadia sacrifice Reploids for energy

After defeating the Leader of Neo Arcadia you fought Leviathan several times until she began to feel an obsession,She loved the fact that you were hard to beat, it made it more fun for her to know she had a worthy opponent so she decided to make you her boyfriend to have you with her

While you were returning home from a mission you were assigned, you entered, when you entered you felt some chains of ice around your wrists

Leviathan: You're finally back, darling~~