Lets go though what happens to Korra between breaking up with Mako and getting together with Asami. 1. She connects with Avatar Wang and discovers the origin of the Avatar 2. She enters the Spirit World for the first time. 3. She is permanently separated from her past lives. 4. She defeats an embodiment of pure evil, that was threatening to consume the world. 5. She becomes the first Avatar in a new cycle. 6. She chooses not to close the spirit portals starting a new spiritual age. 7. She discovers that the Air Nation is reborn. 8. She helps Tenzin begin rebuilding the Air Nation. 9. She visits Ba Sing Se for the first time. 10. She meets the Earth Queen. 11. She encounters the Metal Clan 12. She meets Zaheer in the spirit world 13. She is captured by the Earth Queen 14. She meets Lord Zuko 15. She gives herself to Zaheer to save the new Air Nation 16. She nearly dies when she is poisoned by the Red Lotus 17. She lives in isolation in the Earth Kingdom, trying to reconnect with Rava. 18. She trains with Toph. 19. She loses a duel with Kuvira 20. She mediates into the spirit world with Zaheer, reconnecting with Rava. 21. She assists in defense of Republic city against Kuvira's army. 22. She counters Kuvira's spirit energy weapon, with Energy Bending opening a new portal in Republic City. 23. She persuades Kuvira to lay down her arms and end the war. 24. She attends Varick and Jue-Lee's wedding. 25. She and Asami become a couple. Korra evolved and changed as a character over incredible hardships between breaking up with Mako and getting together with Asami. Its absurd to suggest that she just wants to sleep with everyone.