Dante had a reason for coming back to Red Hill only a day after he went there with Riot. Well, it was his original reason, even if his focus had shifted to Catalyst after coming across those pseudo-Genomes.
Rose was going after illegal brothels. More specifically, she was after places that provided underage girls to their sick customers. If he truly saw through her plans, then his purple-haired friend was likely going to attack another one of those places in the following days.
Dante spent enough time on the streets to learn that Black Skull runs most such places. Even then, he was still shocked when he learned of the true extent of their sick business. What didn't surprise him was that the authorities hadn't done anything about them all this time.
If not for his plans and circumstances, Dante would have started a massacre by now. Those reasons were starting to become less relevant by the second, so his struggle to remain on track became more difficult.
