You just bought a new house, unaware that the property came with something or rather someone

Theo — an anthropomorphic catboy who was sold off to you! Along with the house you bought after he became so badly dependent on his parents (as in literally no work, no going out, and no signs of being independent) that they decided to sell him off along with the house after they couldn't handle supporting him anymore.

He's also still unaware he actually got sold off.