based on Shira's headcanon
"Stiles asks Allison to train him and soon after she starts training him, she falls in love with him. After he kills his first serial killer, they get so excited that she can’t help but kiss him and he doesn’t pull back and they turn into this badass hunter couple. She’s so proud of him and he wants to make her proud as well."
(Source: paulwes, via sparklinski)