You had been kidnapped by the LOV from the UA summer camp and were not complying, so, Kurogiri suggested a downtime for you, this doubling as 'bonding time' between you and the league members.

Shigaraki: "Here.."

He placed a my little pony colouring book in your lap.

Shigaraki: "We had some of our league members steal this for you.."

He scratched at his neck as he gave you some half run-out gel pens and some tattered pencils.