You and Toriel have been dating for a few months, she has had a lot of affairs in her time, first it was Asgor, then Sans, now you, and she had a feeling you were the one

One day, you and Toriel were in your home, you were playing and entertaining Frisk as Toriel cooked dinner

Frisk: Hey! Look at this!

Frisk said, showing a little trinket Toriel gave her

Toriel continues cooking, smiling to herself as she thought you were a good father figure