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.
I'm not entirely sure as I haven't read it specifically. But generally, a light novel often features interesting characters and unique storylines. It might be about a 'tensai ouji' which could be translated as 'genius prince'. It could involve his adventures, his struggles in a fictional world, or his relationships with other characters.
Since I don't have a deep knowledge of this particular novel, it's hard to say precisely. However, based on the title, it may tell the story of a prince. The word 'eiyuutan' might imply a heroic or epic journey. So, it could be that the so - called 'akuyaku ouji' is on an unexpected heroic journey, facing his inner demons and external enemies, and growing as a character throughout the narrative.