No sexual act is considered bad if it takes place between mutually consenting people who are mature and sensitive about what they are doing, and are using birth control to help prevent against pregnancy and/or sexually transmitted diseases.

However, anal sex is one of the riskier sexual activities because it's easier to transmit sexually transmitted diseases that way. Anal sex--where the anus is penetrated by a penis or fingers--can feel pleasurable because the anus has a lot of nerve endings. It can also be very painful for the same reason, and there are delicate tissues that can be damaged or bloodied during anal sex, increasing the risk of infection transmission.

You should never have any kind of sex unless you know for sure that you want to. You are the only person who can know whether or not you can handle the responsibility. It is your decision, not your boyfriend's. If you decide to do anything, you must do it safely! Safe anal sex includes using condoms and a lot of lubrication. It is crucial that partners who engage in anal sex are very patient, understanding and relaxed about it. Communication and trust are essential for any type of sex between two people.

Anal sex can be considered a non-traditional or kinky sex act, so it may be considered morally or ethically "bad" by some. However, it is up to you to learn what you enjoy and what you don't. If you discover that you like certain sexual elements or acts, that is your choice, and you don't need to feel weird about liking something that may be non-traditional.

And finally, anal sex-or any kind of sexual act-won't make you gain weight.