The 25 year old Frenchman made 46 appearances for the Spanish side over two seasons.
"My tattoo has a story but it's not about football", he said about his ink.
Other left-backs had been touted as Everton looked to finally bring their search for competition for Leighton Baines to an end but Digne was swayed by the new Blues power couple after a few months of interest.
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Everton midfield duo Morgan Schneiderlin and Idrissa Gueye also played a part in encouraging Digne to come to Merseyside, while he is excited about linking up with fellow summer signing Richarlison. "I said no to Liverpool two times".
"Since the first day if I want to put one central defender in the game we don't have any".
"I can't explain the feeling but when you speak with a person, you know if it's a good person or not and for me, he's a good person. I'm young and I need to progress".
Silva said Digne is a "high-quality player, aggressive, with good technical ability. he is accustomed to winning".
It is believed that Mina will sign a five-year deal with the Toffees in a deal worth approximately £28 million.