A gentle and sweet-natured soul, Tails was initially timid and lacked courage. After meeting Sonic, however, Tails has become more confident, eventually growing into a more outgoing, brave, independent individual and a hero in his own right. Since encountering Sonic, Tails has looked up to him and stood by his side, helping him whenever he can during their adventures.

Try to use the Japanese actor, Ryo Hirohashi as reference. 

We're also looking for a higher tone with the character, he must have a shy tone but with a little bit of immaturity