MTL - Space Speed Xing Hen - Chapter 31 Threat from the Earl of Vampires (below)

300 years after becoming a Demon King, the war angel Ansel faced a serious problem during a certain expedition.

——His halo grew out once again.

Ansel picked an auspicious place that was definitely and absolutely unmanned, and while cursing, he simply and skillfully broke off the newly emerged angelic aperture.

This thing was growing out faster and faster!

When will his undercover mission end already?!

The demon realm was divided and ruled by three kings. Demon King Saros was forced to go on an expedition with his sworn enemy, Ansel.

One day, he noticed Ansel sneaking away from everyone.

Saros decisively followed him, and was shocked to find that his sworn enemy, another demon king of the demon realm, took off a horn headband and fake bat wings. As Ansel cursed up and down, Saros watched as he skillfully removed a cute halo from his head.

This irritable, easily angered guy who loves fighting; the type that was cute when he shuts up but could make even demons angered to the point of ascending to heaven the moment he opens his mouth…

..was actually an angel???

- Description from Novelupdates

At the moment of her suicide, she was filled with joy, for her great vengeance had been satisfied, and her wishes were fulfilled.Yet, heaven ordained her rebirth before the apocalyptic world.In her past life, she harbored fear towards his possessive imprisonment.In this life, she depended on him, was infatuated with him, clung to him, loved him.Together, they faced ghostly trickeries and walked through the hell on earth, never to be separated again.

A lonely soul, which was placed under the care of the Lord Protector’s Manor, ended up having her lover stolen by the family’s eldest daughter and dying tragically the day before her wedding.

Mu Jingzhe transmigrates into a book filled with sweet, doting love to become the useless supporting character who serves as a foil to the female lead. She also becomes the stepmom of five kids to her recently deceased husband.