Azazel/Relationships

Issei Hyoudou
Issei, at first, hated Azazel because he was a Fallen Angel, but learned later on that he is a good man. Azazel later became the Occult Research Club's advisor in Volume 4, and aided the Gremory team on how to better improve themselves as a team. He also helped out in progressing Issei and Kiba's Sacred Gears, as well as helping Issei learn how to achieve Balance Breaker. He also shows a great deal of concern for Issei after his death but was relieved to hear that his spirit was alive.

Rias Gremory
Azazel and Rias relationships are not clear but seem to have a good friendly relationships.

Akeno Himejima
Akeno initially hated Azazel because Azazel is a Fallen Angel like her father. Azazel, on the other hand, cares a lot for Akeno because she is the daughter of his good friend Baraqiel, but also specifically because he feels guilty about her mother's death. He even protected her behind the scenes during her youth before she met Rias Gremory. Azazel believes that he was responsible for it since it was him who called Baraqiel out on a mission that day, thus leaving Akeno's mother undefended. Azazel treats Akeno like his own daughter and has asked Issei to protect and take care of Akeno on multiple occasions.

Asia Argento
Azazel and Asia relationships are not clear but seem to have a good friendly relationships.

Yuuto Kiba
Like Issei, Azazel helped Kiba progressing his Sacred Gears. Azazel and Kiba's relationships are not clear, but they seem to have a friendly relationship.

Koneko Toujou
Azazel and Koneko relationships are not clear but seem to have a good friendly relationships.

Xenovia
Azazel and Xenovia relationships are not clear but seem to have a good friendly relationships.

Gasper Vladi
Azazel and Vladi relationships are not clear but seem to have a good friendly relationships.

Irina Shidou
Azazel and Irina relationships are not clear but seem to have a good friendly relationships.

Ravel Phenex
Azazel and Ravel relationships are not clear but seem to have a good friendly relationships.

Shemhazai
One of Azazel's closest friends, Azazel cares deeply for Shemhazai while Shemhazai respects him.

Baraqiel
One of Azazel's closest friends, Azazel cares a lot for Baraqiel and feels guilty for having Baraqiel help him which indirectly lead to Baraqiel's wife, Shuri Himejima, death and constantly tries to find a method to compensate Baraqiel. Baraqiel himself doesn't seem to blame or hold any grudge against Azazel, still considering Azazel as his close friend.

Sirzechs Lucifer
Azazel has a respectful relationship with Sirzechs since they were both representatives for the treaty in Volume 4. Since then, they have gotten along, even working together to deal with situations like the Diodora incident and calming Issei down to release him from Juggernaut Drive in Volume 6. They also developed a business relationship for the Oppai Dragon franchise.

Vali Lucifer
Vali was thrown out by his parents due to the instigation of his grandfather, Rizevim Livan Lucifer. Azazel found him and raised him acting as his surrogate father. He sees him as his son, caring deeply for him and he was deeply hurt by his betrayal despite expecting it.

Michael
Azazel has a deep rivalry with Michael even before he became a Fallen Angel. This is mainly because Michael once revealed Azazel's Artificial Sacred Gear's design throughout Heaven and was made fun of because of it.

Hades
Azazel hates Hades because Hades despises the Devils and Fallen Angels. His hatred towards Hades intensified after Hades nearly caused Issei's death by lending Samael to the Hero Faction and Shalba.

Indra
Azazel distrusts Indra greatly, due to Indra keeping secrets about Cao Cao, and suspecting him to be secretly helping the Hero Faction.

Shiva

Azazel talked to him during Volume 19, and he asked him to stop 666 in case of emergency, and he even offered his life for he sake of preventing the destruction of the world but Shiva joked abut his interest on the Irregular Devils and Ophis but he agreed with the condition in regards to the actions of Rivezim Lucifer and the Evil Dragons.

Azazel thanked him for accepting his request but he said it was alright because it is his original role to destroy everything.