I would say Fluttershy, but honestly, I think Cloudy Quartz would fit much better. She's just the right age, and she's a Pie!

(Wonder how she'd react if I flirted with her and then called her mom )

Cloudy Quartz is also pale, like Toriel. I think Cloudy Quartz would make a great Toriel!

Even though Cloudy seems like she could be a good parent, her personality doesn't seem similar at all to Toriel's.

5165102 5165423 I'd say Sugar Belle might fit, possibly even better than Fluttershy.

5165102 For me it's Princess Celestia.

5165102 Princess Celestia for me!