Lucifer Morningstar/Relationships

Charlie Morningstar
Charlie is Lucifer's daughter. In the pilot, it is implied that Lucifer does not believe in his daughter's plan to rehabilitate sinners, with Charlie saying, "I think Dad was right about me," when calling Lilith about her failed interview. According to Faustisse, despite having immense love for his family, Lucifer is not a good father, but he loves his daughter deeply. Nonetheless, Charlie did take his words of dealing with unscrupulous folk to heart, such as Alastor.

As shown in "Dad Beat Dad", Lucifer cares for Charlie deeply and loves her very much. Albeit, he has difficulty showing it and properly expressing his affection for her due to his other issues. Lucifer himself wishes to spend more time with Charlie and desires to feel close to his daughter as they once were when she was child, as seen where he was delighted when Charlie invited him over to her Hotel, taking it as Charlie wanting to spend more time together.

Later, Lucifer himself would show jealousy towards Alastor when the latter began showing his "deep" bond with Charlie for his support of her dreams and goals of the Hazbin Hotel. As shown, Lucifer was obviously threatened by Alastor taking Charlie away from him and was incensed when Alastor pointed how little support Lucifer had given Charlie in her dreams, with Lucifer becoming increasingly insecure of his father-daughter bond with her and began to fight with Alastor to get Charlie's attention.

Lilith
Lilith is the Queen of Hell, married to Lucifer. According to Faustisse, Lucifer and Lilith are absolutely in love with each other. Though little is known about their actual relationship outside of being married (though they are now separated).

Razzle and Dazzle
Razzle and Dazzle were gifted to Charlie by Lucifer during her childhood to act as her personal bodyguards. Razzle and Dazzle are protective of Charlie and the rest of her family.

Alastor
In "Dad Beat Dad", Lucifer showed jealousy towards Alastor when the he began showing his "deep" bond with Charlie for his support of her dreams and goals of the Hazbin Hotel. Lucifer was obviously threatened by Alastor taking Charlie away from him and was incensed when Alastor pointed how little support Lucifer had given Charlie in her dreams, with Lucifer becoming increasingly insecure of his father-daughter bond with her and began to fight with Alastor to get Charlie's attention.

Vivziepop and Dave Capdevielle said that Alastor in no way would be afraid of Lucifer, though Lucifer may be an intimidating character, there's mutual respect going on between them.

Mammon
Mammon considers Lucifier as his "friend". Though little is known whether or not Lucifer affirms this friendship with Mammon.