He continues growling at her, he looks like he's about to bite her head off. Perse very calmly walks past Hades and straight up to Cerberus's main head
She holds out her hand for him to sniff. He does so, big nostrils flaring
Cerberus pauses-and sits, tail wagging furiously, panting happily. Persephone giggles and smiles
"Awwww...who's a good boy!?"
She starts giving him scritches
"Hm?"
She looks over at Hades while still snuggling Cerberus
"Hm? Well who's fault is that? You're the one who's supposed to be training him-plus, he just needs more love, isn't that right sweetheart?"
She says that last part to Cerberus-at this point she's giving him belly rubs