Start in DxD as Motohama: Leveling Up in Another World - Chapter 5: Food from another world. Visit to the library. An unusual new friend.

In a world where its inhabitants can destroy a city wall single-handedly, the empress has a kirin as her pet, and the imperial palace of Great Xia has a pool containing a dragon. There is also a Sword Mountain where spirit swords occasionally leave in search of a master .

Bootlicking the empress, Ren Baqian ascended to the apex of life.

- Description from Novelupdates

Cassian had lived his life in the most miserable way. He had scrubbed the floors and washed the clothes in the cold winter and done everything just to please his uncle’s family, but in return, they sold him to a merchant only for a pouch of coins.And the merchant decided to gift him to the king of Aetherlyn, a faraway kingdom from his small village to show his loyalty and curry favor from the king. And he was the lucky one from the group to be choosen by the king. Thus he got the position of palace servant.Cassian thought maybe his life in the palace would be different, but he was bound to be disappointed as the people in the palace were far more sinister and ruthless. Scheming ran in their blood.And can anyone tell him why his path always crossed with the notorious first prince of the kingdom? The seemingly cold prince had an unpredictable temper. And why was he always drawn to him like a moth to a light?Will Cassian be able to survive in the palace where the true faces are hidden behind masks, or will he become more entangled in their schemes and just become a mere pawn in their game?

In a world where summoners wield the power to call forth vampires, elves, angels, demons, and all humanoid creatures from across the realms, Nathan found himself unable to summon beings except from beasts. However, those beasts are not ordinary beasts. They are divine beings who once stood at the same level, if not higher, than the legendary creatures the world ever knew. Casting his gaze to the left, Nathan sees numerous summoners accompanied by the likes of demon kings, archangels, vampire progenitors, and other legendary beings. Turning to the right, a massive army of alien symbiotes is waiting to attack. There was no fear in his eyes, because standing on his left is a majestic wolf who managed to kill a god, the legendary eight-headed serpent coils on his right, above him is the bird who is glowing like the sun, and behind him is a dragon that once gnawed the roots of the world tree. “Let the war begin.”

When Lucas was having drinks with his friends at a bar a strange girl approach him at a bar and asks Lucas some strange questions.

He didn't think much about that question I mean what could possibly a girl can do and just tell her his ideal world dream but he didn't have thought that by answering this questions, he's on his way down an insane rabbit hole.

But he awaken in a different world almost exactly like his own, but where he have the ability to freely use any woman as he wish for without anyone seeing it as anything other than completely normal, and where anyone will accept any word he say as a truth to be listened to.

Which leaves him only one in this world of casual free use: to become king.