Hey there. First thank you so much for your interest and comment. Fucking love it, that you would love to Marry Mia (Pearls "Step"-Mother). Pearl is definitely increase her corruption with Mom. Looking forward to creating the Quest for Level 2. Mia is gonna get a gear up! Hehe. No Spoilers <3
In regards to your comment above the last one. You actually made me Panic and I tell you why, you said it tells you the Corruption Points are 0. Oh how i trembled. But you mean her level is at 0. Okay, that's not a problem.
In Pearls Bedroom - On her PC - Choose Help - Go to Family - Click on Mia - It will tell you what to do.
If you ever get stuck, its there to help you, to get unstuck also comes with nice Stats Window

Which includes a stat you might look forward to hehe.