Are you talking about BitLocker as the "device encryption"? If so, that is designed to protect the contents of the hard drive "outside of" an authorized connection (such as you pull the hard drive and try to recover its contents from another PC, or booted from an alternate boot device). BitLocker provides no protection to authorized users who have been authenticated on the PC (such as a second user account).
But, having said that.... The files in your profile are protected by the permissions on the files. This would prevent a non-administrator account from seeing your files. On the other hand, if the "other account" was an administrator, then they could alter the permissions and see your files.
I can't tell from you question if you want to grant them access.... or are you trying to prevent access