Only let your conduct be worthy of the gospel of Christ, so that whether I come and see you or am absent, I may hear of your affairs, that you stand fast in the spirit, with one mind striving together for the faith of the gospel. Fight the good fight of faith, lay hold on eternal life, to which you were also called and have confessed the good confession in the presence of many witnesses. The first one is out of love, the last one is out of lust. Love is of God, lust is of the carnal mind and of satan. God is the one who made sex and designed it to be enjoyed in the manner it was intended.
Any different way is sexual perversion.
Like anything whose proper function is abused will cause problems. If oral sex is replacing genital sex it will be even more of an abomination unto the Lord. God has clearly designed male and female bodies for genital sexual relations with each other, not for oral and anal sex. Married couples should beware of substituting something else for that which God had designed at Creation. In this light the practice of oral and anal sex cannot be said to conform with the design of our Creator and should be regarded as deviations from God's design, which are sinful.