In both lives, sadness and agony were his only companion.
Living as Minoru Mineta, the famous class 1-A pervert, he was left out in every task, harassed both by his classmates and his bullies. Loneliness was his constant ally, with his perversion a slight escape from it all. But soon enough, he got what he never deserved, from the people he had fought for, for the people he risked his life for.
Death can truly be remarkable yet sad sometimes.
With those cruel memories, he felt a pit of emptiness enter his heart, that could only be filled with despair of his enemies as he wandered in the Hueco Mundo. In his new life, he rose to be an Arrancar, the Cuatro Espada, Ulquiorra Cifer. But he too met his end at the hands of Ichigo Kurosaki, the substitute soul reaper. But even in his last moments, Ulquiorra understood what it truly meant to have a heart, and hence died with a small smile on his face.
But now given a second chance to go back to where the original world where he belonged leaving someone really important behind, and with his powers of Espada with him, will Ulquiorra Cifer aka Minoru Mineta take the chance, and finally be at peace with a heart?
Kanda Kyoichi transmigrated to Konoha and became a temporary instructor at the Ninja Academy. Fortunately, he awakened the Mentor System.
By teaching others, he could earn rewards.
Thus began Kyoichi's career as a "teacher" in the ninja world.
Shisui: "Sensei's unique interpretation of the Will of Fire has given the Uchiha Clan a true sense of direction!"
Asuma: "The essence of the jade lies in protecting the people, with the advanced leading the way for the less experienced. Only then can Konoha become stronger!"
Kakashi: "He's my life mentor. He transformed Konoha!"
...
Years later, in the memoirs of Kyoichi, now the Hokage, he wrote:
"I honestly just wanted to be a life mentor!"