The harem aspect means there are multiple female characters who are attracted to the MC. In these manga, the relationships can range from simple admiration to deeper emotional bonds. The female characters often have diverse personalities and abilities, adding to the complexity of the story. For instance, in 'Death March to the Parallel World Rhapsody', the harem members include a princess, an elf, etc.
One characteristic is their unique abilities. For example, in 'Overlord', the MC has abilities that are far beyond normal characters in the game - turned - real - world setting. Another is their rapid growth or high starting level. In 'Sword Art Online', Kirito starts with a good level of skills which he further hones.
One great light novel with a powerful main character (MC) is 'Overlord'. The MC, Ainz Ooal Gown, is extremely OP (overpowered). He starts as a max - level character in a game world that has suddenly become a reality. His abilities and strategic mind make him nearly unbeatable.
One great OP MC (Overpowered Main Character) fantasy light novel is 'Sword Art Online'. The main character, Kirito, is extremely skilled and powerful in the virtual world of Aincrad. Another is 'Overlord'. Momonga, the main character, is a very powerful magic caster in a game world that has become a reality. Also, 'That Time I Got Reincarnated as a Slime' is good. Rimuru starts as a slime but quickly gains incredible powers and builds his own nation.
The light novel 'Akame ga Kill!' also has an OP female MC in Akame. She is a highly trained assassin with a powerful teigu (a special weapon). Her skills in combat and stealth are top - notch, allowing her to take on much stronger opponents.
One great anime is 'Sword Art Online'. The main character, Kirito, is extremely overpowered (OP). He is highly skilled in the virtual reality world of SAO. In the series, he also has a love story with Asuna. Their relationship develops as they face various challenges together in the dangerous game world.
There's also 'Death March to the Parallel World Rhapsody'. The MC Ichirou Suzuki is overpowered and gradually builds up a harem of various characters in the isekai setting. The story has a mix of adventure, comedy and some harem elements.
In light novels, 'op mc from start' often refers to an overpowered main character right from the beginning. This means the character has abilities, skills, or knowledge that are far superior to others at the start of the story, which can lead to some really interesting plot developments as they either face challenges despite their power or use it to quickly rise in their fictional world.
I'm not entirely sure as there could be many light novels with an OP (overpowered) main character (MC). It could be about a hero in a fantasy world who has extraordinary powers and uses them to overcome various challenges.