"I am prepared to pay for the termination fee." She overheard their conversation that Theo just took the mission before coming here. So, if he wanted to cancel it, he needed to pay the termination fee because of the loss of time. Even though it was only two hours or so, it was mandatory.
And with the girl paying the termination fee, he could sell the Purple Haze Grass at full price since the former needed the Purple Haze Grass to treat her injury.
In fact, because people often got injured on the other side, Purple Haze Grass was always in high demand.
Normally, one would take pity when they saw a girl going all the way to call him to buy Purple Haze Grass, especially in her condition, but Theo simply ignored her and looked at Raith. "Anyway, this is your three Purple Haze Grass. Please submit the mission."
What Theo wanted was not entirely the money. He also wished to get the Contribution Points, so he could increase his privilege level.