There is a dearth of good sensual masseurs in Boston. I tend to rely on visitors. However, a reliable choice based in Boston is:
https://www.masseurfinder.com/massage-therapists/33896/
I would avoid the following:
Marc - https://www.masseurfinder.com/massage-therapists/37526/
Carl - https://www.masseurfinder.com/massage-therapists/35805/