The Tricolor Fairy Wrasse, Cirrhilabrus lubbocki, also known as Lubbock's Fairy Wrasse. Though the male Tricolor Fairy Wrasse is a bit more aggressive, unlike the females who are quite peaceful. If you are wanting to keep a mated pair, it is better to introduce the female before male. Otherwise the male will become aggressive towards newly added females. 

They will best thrive in a well-established tank, with live rocks cleverly arranged to provide hiding places, as the Tricolor Fairy Wrasse can become shy and may need to take refuge as needed. They are also known for jumping, so it is suggested to have a tightly fitting lid, or top on your tank to prevent escape.