This achievement can be easily unlocked in the tutorial world. Load up the tutorial and complete the basic features so you can go up the stairs. Once you have gone up the stairs you're in a cobblestone 'town' and on the left there will be an opening with some stairs down to where there is farming and animals, go down the stairs and head left. Find the ocelots, you will see a chest that contains fish, take the fish. Let the ocelot out and let it calm down, when it does feed it to it by pressing LT. Love Hearts should appear and you will get the achievement, it might take a few trys to get him to like you.

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