Quite a few things are going to happen. Gu Yangcheon will be punished for the murder of the elder and the subsequent prison break. His father praises him… a little? Moyong Hi-ah will play a role. She makes a contract with the Gu family that is very profitable. In return, she is slowly healed by Gu Yangcheon’s flames. And I mean really slowly—it takes years. That means Moyong Hi-ah will be around with us for quite a while.

His punishment is solitary confinement, which means he has absolutely no contact with anyone and just sits alone in a room. It’s basically an offscreen training arc for the MC. There’s a time skip—I don’t remember how long exactly. But once he gets out, he’ll be significantly stronger. And now, brace yourself: our beloved Wi Seol-Ah has already left the Gu family by that point! It takes quite a long time before she appears again. We might get brief glimpses of her, but nothing more.

After that, I think he goes to the frontlines together with his older sister. Of course, his fiancées follow him, along with the poison girl and the ice girl.

But I’m not completely sure about everything. Some details might be a bit different, or I may have forgotten important information. This is just a rough summary.

Warning: Major spoilers ahead!
Out of remorse for not being able to save his own son, he allowed Gu Yangcheon to kill him. It's difficult to explain, but as we can see, his father isn't particularly emotional. He knew he played a significant role in why Gu Yangcheon became the way he was. The bitter part of the story is that Gu Yangcheon sought out his father not to kill him, but to be killed by him. Otherwise, it would have been impossible for his father to be killed, except by the Heavenly Demon. The two had already fought each other, and his father even managed to seriously wound the Heavenly Demon. Unfortunately, he was also tempted by demonic energy in the process, even though it didn't seem to bother him much.

Sorry for my guilt. This will all happen in the future. So the manhwa didn't skip anything.

Yes he will. His sword is improved by a blacksmith who is possessed by the g** of blacksmithing and who forged the sword as it is now. Afterwards, he can use the sword to create a complete full-body armor made of shadow energy.

The blue phoenix Tess is the king of all phoenixes and the dimension of phoenixes. One could even say that he is on the same level as the G** of Fire as he cannot control Tess's flames and vice versa.

The blue phoenix Tess is the king of all phoenixes and the dimension of phoenixes. One could even say that he is on the same level as the G** of Fire as he cannot control Tess's flames and vice versa.

The blue phoenix Tess is the king of all phoenixes and the dimension of phoenixes. One could even say that he is on the same level as the G** of Fire as he cannot control Tess's flames and vice versa.

The blue phoenix Tess is the king of all phoenixes and the dimension of phoenixes. One could even say that he is on the same level as the G** of Fire as he cannot control Tess's flames and vice versa.