M.E.E.T. ME (Aot/Snk)

Finally eighteen years old, Eren signs up the join the military.
The Survey Corps is a small core built into the Rose Military that conduct special activities. For years, they've been trying to perfect the use of their Mecha Machines, or giant robots, by somehow enhancing their power and the pilots' skills even if only for a limited amount of time; thus the M.E.E.T system was born.
M.E.E.T. stands for the Mental Establishment of an Entity Team.
This system couples machines and their pilots through their entities, making them become aware of one another in ways that would seem almost impossible and powering the robot with two souls rather than one. They merge and become one, suddenly in one mind together, feeling the same pain, hearing the same thoughts, and so much more.
Basically it's as if they're one person altogether; completely aware of everything that is their partner.
Scientist Hanji Zoe is a mind too intelligent for her own good. Except her system has it's holes.
The hard part is pairing up. Partners require the utmost trust in one another; that, or they're in for a whole lot of struggle and pain. And Eren's Altitude test and Wavelength percentage sends him down a difficult path when he matches up almost perfectly with Humanity's Strongest, who for years has been rejecting every partner he's ever been given.

WARNING: This story includes sexual content between males.
And death. Yay.

Levi/Eren
One sided Eren/Armin
Past Jean/Eren