Sexual favors

They'd known each other since season 3 of station 19, there were always feelings and emotions between the two, but instead of facing those feelings; they bury them into the satisfaction of the other's body. And even though this dynamic works for them, keeping it a secret for everyone including their co-stars is s struggle. But one of the biggest obstacles to come seems to be that this agreement was to burry their feelings, but in return it only makes them stronger.