A fulfilled promise (Eremika)

The Survey corps are in reach of wall Maria. An army of titans stand between them and the wall. The brave soldiers charge but are being defeated. Eren has feelings for Mikasa and so does Mikasa but they aren't telling. What happens when something happens to Mikasa in the caos of the battle? Will Eren fight or breakdown? Will Mikasa die or live? One promise stands between life and death.