I'm not sure specifically as there could be many different stories with this title. It might be about a prince in a reincarnation or isekai setting which is a common theme in light novels.
Power and its implications are also important. He gains certain powers and has to learn how to use them responsibly and also deal with the consequences of having power in a world full of different factions and interests. In this light novel, there are often situations where power can be both a tool for good and a source of trouble.
Some local libraries might also have it. Check with your library's catalogue, either in person or online. If they don't have a physical copy, they might be able to get an e - copy through inter - library loan.
Another option might be 'Overlord'. The story follows a powerful character in a game - like world which has some parallels to the unique situations often found in 'Tensei Ouji wa Daraketai'. For example, the exploration of power dynamics and character growth.
One possible theme could be unrequited love. The title gives the impression that one character has feelings for another who might not be aware or reciprocate right away.
I'm sorry, I'm not very familiar with this light novel specifically. But generally, a light novel often has unique characters and an interesting story. It might be about some kind of relationship between the characters where one has an unexpected or special feeling towards the other as the title seems to imply.