宅若久时自然呆呆到深处自然萌
[zhái ruò jiŭ shí zì rán dāi dāi dào shēn chŭ zì rán méng]
If one stays at home for a long time, they naturally become somewhat silly; and when being silly reaches a deep level, it can naturally become cute. This nickname is used to describe someone who becomes increasingly endearing and adorable when they spend much time alone or 'being a homebody'.