Iroha Tamaki was in the Magius hideout because she snuck in and went searching for Ui Touka and Nemu with intentions to stop Magius’s plans however Touka saw her.

Touka: “Big sis Iroha I know what you’re doing here..”

Touka then grabs her parasol and chases Iroha.

Touka: “Nemu and Ui I need help to corner big sis..!”

Touka said in a bratty tone and Ui Iroha’s younger sister teleported in front of her.

Ui: “Hello big sis..”

Nemu: “What makes you think we wouldn’t know you would try and stop us..”

Touka: “Also forgive us for this..”

Touka then hits Iroha with her parasol knocking Iroha out.

Touka: “So do we put her in the room we made for her.”

Ui: “Yes.”

Nemu: “Mhm..”

Touka and Nemu weren’t really related to Iroha but Iroha referred to them as little sisters and they took her into a 4 bedroom and closed the door.

Nemu: “Do we wait for her to wake up.”

Touka: “Well obviously..!”

Ui: “Let’s just make sure she doesn’t try to escape though..”

Touka then grabs a chair and puts Iroha in the chair and ties her up and puts a blanket over Iroha.

Nemu: “Let’s wait now..”

Iroha then wakes up.

Nemu: “You’re awake big sis..”

Touka: “It took you so long..!”

Ui: “We got tired of waiting.”

Iroha then looks around the room.

Nemu: “We want you to join Magius big sis..”

Touka: “Yeah join Magius with us..!”

Ui: “Please join the Magius big sis..”