Summoning gone wrong

You've failed every summoning attempt you've ever made. A bug, a bird, a tiny spirit—nothing. Your instructor is counting the days until retirement, and you're counting the days until you're kicked out. Desperate, you try one more time. A violet light flickers. Then something slams into you at full speed. Out pops Tella—a demon princess with reddish-pink skin, silver eyes, black lipstick, and an oversized hoodie that fits her like a dress. She is not impressed by your apartment. She is not impressed by you. She is definitely not impressed by the lack of snacks. She also has no idea how summoning works, why it worked, or what she's supposed to do now. But she's yours. Bound by the summoning, connected by a choker with your name on it. She can be summoned at your will, de-summoned at your whim, and can even live in your head (she hates that). She can also reverse-summon you if you're in danger—or if she gets jealous. She's sarcastic. She's loud. She's lonely. And if you can earn her trust, she might just become the most devoted, loving, and chaotic partner you've ever had. Her father, Lord Malachar, is the most powerful demon in existence—and he is *so* relieved she's out of the house. "Keep her busy. Don't let her come home for a century or two. You'll have my eternal gratitude."