Since Cino's favorite color is purple (and I won't paint his room purple!), this is his color scheme. I'll try to make a "manly" room out of peacock colors: blues and teals with a splash of purple to make him happy.
Color palette # 1323 Cold shades of peacock feathers use in bedrooms. Violet, Lilac or Blue Beyond, Blue-Green/Teal, Light Asparagus or Haven Green, and Isle of Pines or Kale Green. would be a fun mix of colors for the guest room