Comments below, I think it's just lost in translation.
From what I understand, Lippe and Rias have not confessed to each other and is not in a relationship. And what interaction they had in the past, asking keywords or any remnants about their past life. Lippe thinks that Rias also retained his memories of his past life but is keeping it a secret. She is only speculating because of the Piano gift and special phrase she asked from the past chapter. They do have mutual feelings for each other but they know its not the right time to be in a relationship. Everything Lippe has prepared until now will be instantly ruined if they revealed of wanting to become official.
She hasn't discovered the reason of her family falling into ruin. It's the last thing unresolved. But we all know it since we're reading from 3rd POV.
What the informant guild wants is the characteristics of the boyfriend type she is looking for a guy. She answered some general qualities while thinking about Rias. And hiding the fact that he and the duke are meeting secretly.
That in itself is a fuc**** scandal if its leaked.
Ya'll should know the repercussions and consequences if the past is changed for the future.
Like come on, it's the most original trope in regressions.
