It sucks despite the heartwarming moment that at the back of my head I keep thinking that a few years later in-universe it'll be an older Marisa master sparking them.

Could be a callback later on if Marisa mastersparks Kagerou in the face and she does that hair thing again.

But Master Spark is the best way to make friends (except maybe Fantasy Seal). Even in this manga - Marisa and KageWaka acquaintance started with Master Spark (v.5).

ftahgn said:

It sucks despite the heartwarming moment that at the back of my head I keep thinking that a few years later in-universe it'll be an older Marisa master sparking them.

Could be a callback later on if Marisa mastersparks Kagerou in the face and she does that hair thing again.

This. There must be a whole sequel starting with this.