I swear she's like a glutton for punishment.

Anyway, in the original, Sky makes a pun with Messer and "messa" (pronounced the same), basically a dialectical (mostly Kansai) pronunciation of meccha ("very", "extremely")

Spring decides to carry on the pun by also 'slurring' "metta" to "messa" (not a common pronunciation, but the consonants are close enough). "Metta" in this case means "rarely (seen)", when combined with negative grammar.

This of course pissed Sky off.

Not sure how to translate this pun though... best thing I can come up with is to slot in "messer" in place of "rather" and hope people can catch onto it. Not as intuitive (or funny) as the Japanese original though.

Edit: Going with "it hardly messers" for the second pun.