Galatians 5:12 says: "But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control."
The conjunction "BUT" is a key word that I have often missed when reading this verse. The word is used to join another phrase or idea to show contradiction. In the context of this verse, in contrast to the fruit of the Spirit are the desires of the sinful nature. (Gal 5:16-17: "So I say, live by the Spirit, and you will not gratify the desires of the sinful nature. For the sinful nature desires what is contrary to the Spirit, and the Spirit what is contrary to the sinful nature. They are in conflict with each other, so that you do not do what you want.")
Incidentally, Paul was speaking to the Christians in Galatia. Non-Christians often have a false expectation that all Christians are immediately "goody two shoes". Clearly from the above verses, all Christians are warned not to gratify the desires of our sinful nature. We all have a sinful nature, Christians and non-Christians alike. Here is what is opposite of the fruit of the Spirit. Gal 5:19-21: "The acts of the sinful nature are obvious: sexual immorality, impurity and debauchery; idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions and envy; drunkenness, orgies, and the like. I warn you, as I did before, that those who live like this will not inherit the kingdom of God." Note that Paul's reiteration was to the Christians: "I warn you, as I did before....." Christians, like non-Christians, are just as vulnerable to the desires of our sinful nature. The difference is that we have crucified the sinful nature and Paul exhorts us to now live in step with the Spirit.