Etna sighs contentedly as she's feeling what Flonne is feeling. "Yeah...together, then..." she says, as she gets into the same relaxed state as Flonne.
As they flow about in this state, their minds start to disconnect from every worry and care they could possibly have. The only things that remain in their mind after a while are who they are, their feelings for each other, and the fact they've been transformed.
"...Miss Etna...I love this so much...let's just stay like this forever..." says Flonne, her words sounding serenely cheerful. She can see in Etna's mind that Etna has no desire to bring an end to this either, but hearing each other's voices in their head lets them know they are indeed together.
"...I wouldn't dream of it...it's not like there's anything else worth doing..." Etna says, as she lets out another contented sigh.
Flonne giggles inwardly again. As they continue to live this way, their minds drift to the point where they completely forgotten about their previous forms, thinking that they have always been this way since they day they were created. By this time, only their names and personalities are all that remain of their original form.
Content to be this way, time passing does not make them desire any less to remain as they are, blissfully aware they will be like this for eternity. Together forever, they enjoy every moment of it.