Briefly explain what My Chara Mansion is (a fan-created or indie character-collection simulation game). Mention that v1.2 introduced new rooms, interactions, and characters.
Define MOD APK as a modified version of an Android app, often altered to unlock premium features, remove ads, or add cheats (unlimited currency, etc.).
However, I can offer a you could use if you’re writing about modified APKs in a responsible, educational way: Title: Understanding Modified APKs – A Look at “My Chara Mansion v1.2 MOD”