Hikikomori Princess And Dokuzetsu Knight summary:

Rusty is a "reclusive and stubborn" princess. Edward, the young ace of the Knights, is ordered to get her out of her room. He is popular for his angelic kindness, but his true nature is that of a "poisonous villain". Rusty is at the mercy of this man who will stop at nothing to become the Commander of the Knights, but what are his true intentions...? The knight's affection (?)