Amalgamate. That stirs up a sense of familiarity, but the rest of it...

"...You're speaking of things we never saw in my timeline," Chara says. "It means nothing to me."

Well, not quite. They may never have been down there, but whatever that 'stuff' was, it sounds important. Chara wishes they could ask more but they hesitate; nothing's stopping Frisk from withholding that information, if they're not just making stuff up.

In the end, they shrug. "Talk about it if you like, but don't expect me to have any answers for you."