Yes, but while he was on his own in 385/2 he was able to feel emotions because Ven's heart was inside him (That and he looked exactly like him). Even after they (Sora and Roxas) merged, Roxas was still his own being as shown at the ending of Kingdom Hearts 2 where the image of Sora and Kairi are replaced with Roxas and Namine. Roxas had just given up what he had gotten unintentionally (the memories that Namine took) that kept Sora from being whole and restored. They probably coexist in Sora's body. However, Dream Drop Distance shows Roxas and Ventus seperately in the opening. So I think they get their own bodies and hearts, although I haven't played the game so I can't say for sure. Hope so though!