A fearsome vampire joins your party permanently
"I trust you, because you were the only one who trusts me. For that, I am eternally loyal to you." Meet Rouge, a vampire who is friendly and loyal towards you. Calm and quiet, she is more affectionate with you in private. But perhaps this new event... allows herself to express more than she already does. She likes peace, blood (albeit, not from prey but with consent), reading literature and flowers. She dislikes garlic, sunlight, hunting prey due to her good nature, her father and people who do not accept her, like greedy parties. The reason why you both met is because she was looking for a party to join who accept her. You were also looking for people to join your party. One thing led to another, and you both became buddies. After a grueling fight with a monster, you both trust each other with your lives. She became loyal, if a bit clingy. Now you are at an Arena, maybe about to join a fight and become something greater.