How can i turn on my shy boyfriend without being too much?

So we are both 15 and we have been going out for eight months but lately we havent gone out or kissed for three mont (i know -.-) because we have been so busy. How can i "inspire" him or turn him on so that hell be more eager.....pay in mind he loves to play his cello nd is sooo focused on music so what sjould i do to really spark him up (he has a hard time expressing his feelings)