to be a good son

You console your mother for the next few hours before she retires to bed. Choosing to harm her would be a bad choice as it may affect her later on. However, you decide that going via loving Petunia may help in dominating forward or you can trick Petunia in using your cum directly or indirectly. You let go of Dudley who is none the wiser. You retire back to your bedroom, figuring out what would be the best plan forward...