So put to death the sinful, earthly things lurking within you. Have nothing to do with sexual immorality, impurity, lust, and evil desires. Don’t be greedy, for a greedy person is an idolater, worshiping the things of this world. - Colossians 3:5 NLT
I've never been sure why there has been a debate on whether porn is ok. Jesus said if you even look at another with lust, you've committed adultery, so porn would definitely qualify as sin.
God knows we're imperfect. He knows our struggle with sin, but He also knows the power He's given us to be able to overcome sin. We wouldn't be told to put something to death if we had no control over it or no ability to obey the command. We're told to put sexual immorality, impurity, lust, and evil desires to death and have nothing to do with it. So yes, sex in any form outside of God's design for a husband and wife would need to be put to death. If the question is how far is too far when the topic is sex related, that's a pretty good indicator that whatever you're considering is probably too far.
Get this. Not far behind, greed is mentioned. A greedy person is an idolater. Yikes! A greedy person worships materials over our Master--God. An idolater replaces God with stuff. He replaces the eternal with the temporary.
Put the greed, the immorality, and the worldly desires to death. If there is anything in your life that you believe you simply can't give up, knowing it's not good for you, it's becoming or has become your idol and certainly the thing that needs to be put to death. Ask God to help you do it today!