Apocalypse: Cold Commander? It's My Boyfriend!

[Dual male protagonists + double cleansing + pure love + white cut and black + strong + apocalyptic + rebirth + superpowers + infrastructure] Guarding the restricted area, the forbearing and affectionate commander Gu Jinran Xi Xuci was betrayed by a trusted ally in his previous life. He was used as a living bait for monsters that broke through the restricted area. He spent his life in the ruins of Eternal Night and was unexpectedly reborn after his consciousness disappeared. Good news: He is back again, out of the trap of death, and has all the information about the future crisis! Bad news: Gu Jinran, the commander stationed in the border restricted area, has already drafted the documents to terminate the partnership contract. Xi Xuci thought that Gu Jinran had always been rational and restrained, with a clear distinction between public and private matters. Only after the two re-established their bond did they discover the other's uneasiness and obsession hidden under the calm shell. Birthday gift version "What's today's date?" "... Twenty-nine." … "Send me to myself." … "Whose birthday is it?" "Mine." "Who sent it?" "You." "Who am I?" "... Brother." … "Aci." "Yeah." "Happy birthday." … "More next year." "Okay." "The year after tomorrow." "Okay." "Every year." ~~~~~ "Aci, catch me and take you home." "Ah Jin, thank you for your hard work, welcome home. Even if you fall into the bottomless ruins of eternal night, I will travel to all dangerous areas and take you back to our home.