Dual Soul One Body

A man playing video games in his apartment is interrupted when a girl breaks through the wall. She is his neighbor but lives in a space connected by a dimensional rift, filled with a dungeon-like structure. The girl, named Kris, is being pursued by succubi and claims that unstable magic in her world occasionally creates portals to his. Within her resides another entity, Seres, which emerges when she drinks a potion made from her ring, altering her appearance and granting her significant strength. The man, now stranded in this alternate dimension, must travel with Kris and Seres to find a way back to his own world.