The Reapers are a machine race that are highly-advanced. They are powerful, wiping out the Prothean race fifty-thousand years ago. Many believed that the Reapers are simply a myth, a rumor. There had been no sightings of them by the current living races, so nobody bothered to prepare for an attack by one. And here she was, watching Shepard fight against one by himself.
A hand rests on her shoulder and she turns to see the familiar face of the turian who has been by her side from the beginning. "Don't worry, Tali. He's Commander Shepard, the human who has defeated Sovereign and fought in a suicide mission against the collectors. The Quarian Fleet is aiding him. He will make it through this."
He was right. Shepard was the one to save her life on the Citadel by a group of assassins, along with this very turian named Garrus. She aided him in return and then joined his squad with the original intent of fighting against the geth, a creation by the quarians that rebelled. They were the reason why the quarians were driven from their homeworld. The quarians have weak immune systems, so being banished forced them to wear suits with masks to protect themselves. Since then, Tali has been by Shepard's side through just about every obstacle and hurdle, from fights against the geth to a suicide mission against the collectors. But it was all worth it.
After all, Shepard is her boyfriend. She loves him.
She looks back at Shepard as he narrowly avoids another beaming attack by the Reaper. Watching this battle is nervewrecking. Helping him would be counterproductive, though. This was a one-person job to target the Reaper for the quarian fleet and adding additional people onto the battlefield would simply make things harder for Shepard than it already is currently. She watches as he aims his gun at the Reaper's weak spot again in order to signal the fleet. The weapon locks on and the fleet strikes again. The Reaper falls this time.
The quarians are free to call Rannoch home once again. The geth have even stopped rebelling and now obey the quarians. Tali could almost not believe it. Shepard approaches Tali and sits by her side. "I am sure it will take getting used to allying with the geth on Rannoch, won't it?"
Tali looks at Shepard. "I'm coming with you." Before Shepard gets the chance to speak, she continues. "You have helped me numerous times against the geth. Not to mention, if it was not for you, the quarians would still be without a homeworld. We now have Rannoch back and eventually the Reapers will return. After all, you just killed one. I want to continue to fight against the Reapers with you, Shepard."
She stands up and takes off her mask and takes in a breath of Rannoch's air. "This is worth fighting for."