Both red and pink denote love but while red is hot passion, pink is romantic and charming. Use pink to convey playfulness and tenderness.Multiple shades of pink maintain the soft and delicate nature of a person.So why do ppl always say "Pretty in Pink",bcuz pink is the sweet side of red.Thus pink has a strong msg of romance,charming & tenderness.It stands for beauty, grace and goodness.
Here's a random pix of pink:
