Date a live: Bloodlines

Shiori Itsuki was a normal high school girl, living with her little sister Kotori, ln a world with a strange unknown phenomenon called spactial quakes, That apper at random, and destory everything in their wake. One day during a spactial quake, Shiori went out to look for her little sister, only to find a strange girl in pink armor, fighting against a group of girls wearing somesort of battle suit. During this event Shiori was knocked unconscious, and later awoke in a medical bay with a woman named Reine, who explained to Shiori that she was on a ship called The Fraxinus and toke Shiori to the commander of the ship, who was revealed to be Shiori's own little sister, Kotori. Kotori explaned to Shiori that the girl in pink Armor was a spirit, a female race of beings from another dimension, of which when brought into this world, causes a spactial quake, and the girl's who were fighting her, was a anti-spirit group called The AST, a special unit tasked with suppressing, and killing Spirits. But there was a way to save the spirits. Unknown to Shiori, she was born with the ability to seal a spirits power by making them fall in love with her, then kissing them. Initially hesitent about this, however Kotori convinced her sister to do it, and together they were able to seal many spirits, and even make friends with them. Till one day, Shiori met a man..who would change her live forever.