Gabriel Agreste/Hawkmoth is the main antagonist of the series. While he is a big deal in Miraculous Ladybug, he does not show up too often in the comics. First line is Hawkmoth, second is Gabriel, and the third is what is usually seen in comics.

Gabriel is a top fashion designer in Paris and the father to the main character, Adrien. He is often busy with work and tends to neglect his son. While he may not give time to Adrien and puts him under strict parental vision, he does not mean to hurt his son. He is quite cold and collected. His assistant is Natalie and she knows his true identity. He is married to Emilie but, it is unknown why she is unwell. She seems to be alive, but unconscious. Theories say that he wants to collect the miraculous to bring his wife back. 

As Hawkmoth, his voice is a little more lively. He "akumatizes" people by sending out butterflies. These butterflies find negative feelings of others and attach to one of the items they are wearing or carrying. They use their negative feelings and gives the person the power to transform into something related to the problem they have. Hawkmoth communicates with them and persuades them to steal Ladybug and Cat Noir's miraculous in exchange for getting revenge and/or keeping their power. He has the kwami Nooroo and a broach as his miraculous that he stole.