taken from the Valerian Military Wikia
Dean Valeria was one of Beatles' original teammates, and also one of the well-adapting adroit fighters in Beatles' army.
Dean's personality is rather lazy, and is not greatly active to his military duties. However, when the time arrives, he is fiercely loyal, and is ready to stand in front of the line. He is one of the people that Beatles trusts, and is relied on many times.
During the Bavarian era, Dean Valeria is first found by Leo Valeria, who was willing to train Dean to the next level. Beatles decides to create a match between Dean and Ivy to see who would be most suited for his top 10 members, which never happens. However, Dean is considered by Beatles to be the top 10 due to his loyal personality and skills.