Soulmate - Dean/Castiel

"It's no ordinary necklace, you see," she would always say as she brushed my hair before putting the necklace on me. "This necklace is special. This is only one half of the necklace. The other half belongs to the person who you are meant to spend the rest of your life with. The other half, my handsome Dean, belongs to your soul mate." - with minor Sam/Gabriel