All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
The people of Loot (Lot) committed Shirk, as evidenced by the hadeeth in Saheeh Al-Bukhaari narrating the story of Ibraaheem (Abraham), which includes the following:
Once upon a time, while he (Ibraaheem) and Sarah (his wife) were traveling, they passed by (the territory of) a tyrant. Someone said to the tyrant, "There is a man here who has a very pretty woman with him." So he sent for Ibraaheem and asked him about her, saying, "Who is she?" Ibraaheem said, "She is my sister." Ibraaheem then went to Sarah and said, "O Sarah! There are no believers on the face of the earth but you and I. This man asked me about you, and I told him that you are my sister, so do not contradict my statement." The tyrant then sent for Sarah, and when she entered upon him, he tried to grab her with his hand, but (his hand became stiff and) he was confounded. He asked Sarah. "Pray to Allah for me and I shall not harm you." Sarah asked Allah to cure him, and his hand was cured. He tried to grab her again, so (his hand became stiff and) he was even more confounded. He again asked her, "Pray to Allah for me and I will not harm you." Sarah again asked Allah, and his hand was cured. He then called one of his guards (who had brought her) and said, "You have not brought me a human being, but you have brought me a devil." The tyrant then gave Haajar as a girl-servant to Sarah. Sarah went back (to Ibraaheem) while he was praying, so he gestured to her with his hand, as if asking, "What happened?" She said, "Allah has foiled the evil plot of the infidel (or the wicked one) and gave me Haajar for service." [Saheeh Al-Bukhaari 4/141]
Ibn Al-Qayyim wrote, "The people of Loot, along with their Shirk, committed unprecedented lewdness (sodomy)..." [At-Tibyaan fi Aqsaam Al-Quraan, p. 25]
He also said:
"Passionate love (immoderate love exceeding the proper bounds) of prohibited images is a form of worship; rather, it is a higher form of worship, especially if it took over the heart and overwhelmed the person. He worships his beloved (be it a person or an object). As such passionate love intensifies, it evolves into worshipful love (Tatayyum), which implies worship. The person is overwhelmed by his worshipful love, longs for his beloved, and seeks his pleasure. He gives priority to the remembrance of his beloved and winning his pleasure over the pleasure of his Lord and avoids incurring his wrath more than he avoids incurring the wrath of his Lord. He strives, exerts efforts, and takes great strides to gain the pleasure of his beloved, obey him, and draw close to him. He favors his beloved over his Lord in terms of love, submission, and obedience. Therefore, passionate love and Shirk are intertwined. Allah, The Exalted, highlighted the passionate love of the polytheists from the people of Loot and that of the wife of Al-‘Azeez when she was still a polytheist. The more the Shirk of a person intensifies, the more he is afflicted with the sinful worshipful love of prohibited images." [Ighaathat Al-Lahfaan min Masaayid Ash-Shaytaan 1/64]
For more benefit, please refer to fatwa 36061.
Allah knows best.