The☆Lukeman is a manga written by Lucidien "Luke" Kallister in his childhood in Yu-Gi-Oh! SEVENS. It is based around an author avatar of Luke who becomes "The☆Lukeman". The character and manga later serve as the basis for The☆Lukeman while it is controlling Luke. Luke himself regards the manga as the most embarrassing thing he's ever done; its publication in the Goha #7 Elementary Newspaper cowing his ego after becoming the King of Duels.
Something fell from the sky, killing "Mr. Dragon" through unknown circumstances. As he died, Mr. Dragon entrusted Luke with a card. An evil Ruler later appeared, and Luke used the card to fuse with the remains of Mr. Dragon to stop him, becoming "The☆Lukeman". The story also appears to involve a character based on Luke's older sister Haruka "Tiger" Kamijo called "Majin Tiger".
These events are later replicated when Luke finds something in the forest after trying to watch the Goha Meteor Shower. He falls under the control of a Goha Enterprises Drone, which refers to himself as "The☆Lukeman". During his Duels, The☆Lukeman uses "Fusion", a card originally known to have come from space, to fuse his ace monster "Multistrike Dragon Dragias" with "The☆Dragon" into "Superstrike Dragon Dragiastar F". This is likely deliberate on the part of The☆Lukeman due to being created from the manga's data and desiring to "fuse" with Luke to fight evil.