Are there novels similar to "The Reader and Protagonist Definitely Have to Be in True Love"? When ML is OP, but cold and cruel, because everyone shies from him for one reason or another, but he melts because of MC, who accepts him wholeheartedly. It would be awesome if the novel had a Transmigration or Time-travel trope.
The only ones I could think of off the top of my head are Reborn into a Slash Game: Readers who loved "The Reader and Protagonist..." also loved this one. It shares similar themes with a cold and cruel ML who slowly warms up to a caring MC. Also includes the transmigration trope. The romance is also fluffy and the two care greatly for one another, which can be seen through their actions. Highly recommended for you. ML is OP, good at fighting. Picked up by the Protagonist of a Tormented! MC novel: MC transmigrates into a world where he helps the protagonist so he doesn't grow up to be coldhearted. Personally, for me, the beginning and middle were good, but the ending was utter bullshit. ML slowly grows to be OP, but he's still powerful. Transmigrated into a School idol and forced to do business: Modern times, MC transmigrates and tries to cozy up to the coldhearted ML for a better future because the original host's original ending wasn't looking so good lol. ML is cold/indifferent to him but his heart is slowly captured by the sweet and innocent MC. ML is OP, he's rich LMAO There's a lot more, but my mind is blank right now. Hope this helped!
https://www.novelupdates.com/series/after-brushing-face-at-the-apocalypses-boss-for-363-days/ https://www.novelupdates.com/series/my-husband-is-suffering-from-a-terminal-illness/ Supposedly cold MC, but he's just an awkward little mouse around MC
You can try these, I found them pretty similar. Idk how to attached link, but you can just search the title in NU. Btw they are both transmigation. - The Disabled Tyrant’s Pet Palm Fish - Every Day the Protagonist Wants to Capture Me Or you can go see the recommendations list on the novel page, usually they also have the same/similar theme. Hope this helps!
The Scum Villain’s Self-Saving System Transmigrating into a Mob Character to Rehabilitate the Villain Plan Who Dares Slander My Senior Brother I’ve Led the Villain Astray, How Do I Fix It?
https://www.novelupdates.com/series/tyrant-pampering-wife-diary/ https://www.novelupdates.com/series/the-disabled-tyrants-pet-palm-fish-transmigration/ these seem similar to your description!