Stellar Echo: Heart of the Myst - Chapter 86: VOL 2 : Elara Belmonte.

Vincent Strider was a gun for hire who made a living by killing whoever it was his clients wanted dead. But during one mission, he died in a fierce gunfight. However, death was not the end for him. Vincent found himself reincarnated in another world, facing a floating interface that flickered before his eyes.[Synchronizing Host!][Military System initializing.]Vincent found out that in this system he received, he can summon soldiers, tanks, aircrafts, and even warships! This is going to be exhilarating.

In the year 241 of the 6th era, Constantinople was in turmoil.Emperor Constantine personally lead his army, which was completely annihilated. The pagan empire, riding on the wave of a great victory, annexed the entire eastern territory of the empire, and its military might pointed directly at the capital.The 17-year-old imperial princess Theodora ascended the throne in crisis, facing what was already a terribly damaged realm.Rome was about to fall.....................The wheels of fate spun wildly as a transmigrator appeared on the streets of Constantinople.“According to the original plot, it was only a matter of time before Constantinople would fall.” he pondered.“Perhaps I should first whisk away the empress.”(The book is categorized under game fantasy worlds, set in a magically altered Middle Ages, and another title is 'I Really Can't Lead This Team')

Yu Shanshan, who has been tyrannical and lawless for 20 years, suffered retribution at the age of 21. She changed from a little ballet princess of 45 kg to a poor and fat one of 90 kg.. Apparently, eating was the most important thing in her life. Her success in losing weight was far away.

However, one day, the father of her child who had disappeared for four years came back. From then on, Yu Shanshan was forced to embark on a diet that was worse than death.

- Description from Novelupdates

Takahiro Nao, a 25-year-old burdened by crushing debt and driven solely by his love for his struggling family, meets a tragic end—until a mysterious Goddess of Benevolence offers him a second chance: reincarnated in another world, and his efforts there will provide for his family back on Earth. Awakening in the body of Naoki von Blackmore, a disgraced “Failed Hero,” Nao is thrust into a realm of sword and magic, monsters, and war, tasked with the impossible mission of defeating the Demon King. With newfound powers, a shadowy past, and the weight of two worlds on his shoulders, he must battle not only relentless enemies but fate itself. Blending emotional depth, thrilling action, moments of humor, and a spark of romance, this gripping isekai adventure asks: how far would you go—and what would you sacrifice—for the people you love?