Keima vs Core 219

Keima was kidnapped by Hugo while he was influenced by Dungeon Core Number 219.

Beforehand
Keima was bodyguarding Mai when he was kidnapped.

Core 219 wanted Keima as a hostage against Haku.

She was watching Keima ever since he stepped into Tsia as it is her territory. She saw his succubus form and {Ultra Transformation}.

In the Dungeon
She threw Keima and Hugo to a jail cell. Where Keima used his Ultra Skill to get out, than succubi transformation to get some clothes. As Hugo has seen it he broke out from the Jail using his too OP skills or whatnot.

After the prison break, they encountered numerous monsters but they took care of them. They found a stream and followed it leading them to a Boss Room. Where they had to beat a Giga-Plant. They successfully beat it with weedkiller which Keima bought with Dungeon Points. After that Keima wanted to pour the same weedkiller into the stream. As soon Core 219 realized what he was trying to do she tried to stop him. But she couldn't do a thing.

Aftermath
They made a contract using {Trinity}: Keima doesn't tell Haku about her revolution
 * You guide us out of the dungeon.
 * You don’t come after me again.
 * Don’t tell anyone about my Succubus transformation.

He made a {Trinity} contract with Hugo as well, asking him to search for information about the Divine Beddings.