[Naruto | All Tobirama] Out of Place

This is a tragedy.

In my headcanon, Tobirama lost one eye while developing a jutsu.

To investigate the Mangekyo, he decided to kill Izuna and take his eyes.

Izuna deliberately held back and died by Tobirama's blade.

After much inner turmoil, Madara decided to give Tobirama one of his eyes.

Later, Tobirama discovered that the power of Izuna's Sharingan was "being able to see what the other person is thinking."

Izuna had long since seen Madara's feelings for Tobirama. For Tobirama's eye, Madara's eye, and the future of their two clans, Izuna felt that his death was absolutely worthwhile.

Tobirama was devastated. Only after Izuna died did he realize that "Uchiha Izuna" was very important to him.

Madara never confessed his feelings for Tobirama before leaving the village.

Hashirama filed his feelings for Tobirama under "brotherly love."

In this life, Senju Tobirama had nothing and found no place where he belonged.

Everyone has unrequited feelings for Tobirama, while Tobirama has just the tiniest, tiniest hint of feelings for Izuna.

The above is more or less the whole plot outline. I may not write the Fourth Great Ninja War. I might write a HashiTobi chapter, a MadaTobi chapter, an IzunaTobi chapter, or possibly some short bonus stories.