A novel I read way back, when BL stories were only a few. It was a quick Transmigration with a system. They were fighting against an AI, and the love interest was trapped inside. The MC knew how to hack. I think it had a blue cover. It's currently completed
Hmm is it Quickly wear the Face Of the Devil? MC is a hacker, trapped inside multi-worlds set up by this sentient super AI. Later, he comes out but his lover who accompanies him in every world is inside the multi-worlds... But the novel cover is blue so I am not really sure...