Males get erect for a reason. They may seem unwanted to you guys, but not to the body. If it's not a bother to you, allow him to enter you (vaginally). The semen lost during masturbation could be inside of you for purposes of procreation. The more he gets to ejaculate inside of you, the more those painful erections will subside (and the better your chances of becoming pregnant). The erections are a subconscious body statement that he really wants to reproduce as well as that he is boiling with unexpressed creativity that only has an outlet via sexual intercourse. The more intercourse, the more those erections will subside. Or, he must learn to channel his sexual desire up to his higher charkas via yoga and other measures which would stimulate his pineal gland and crown center. Doing this, he'd become more spiritual and intuitive. You guys might also want to consciously have intercourse at night as the night-time (moon) supports conception. Go with the flow of Nature! Please check some of our articles on Men's Health.