I highly doubt this would happen (although I would love it) but here goes: Penny/Bolt: Love is Loyal
Are you able to use the same tagline but for an entirely different pairing? Say Person A uses Princess Banana/Prince Peach "Love is a Toaster". Could Person B use Princess Whammy/ Prince Bammy "Love is a Toaster" too?
Cinderella/Prince Charming - "Love is Transforming"