I uh...am not sure if that was a good thing or a very bad one.
So the lambda is a good ghost?
You can interpret it in multiple ways.
My personal take is that the local god / Spirit might have been forgotten and left weak. ( assumed from the state of the shrine )
But thanks to her offering he got some power back.
( and also a new appearance in the hope of attracting more attention? )
Another interpretation could be that since MC´s friend's aura is so powerful.
It more or less transforms the local Spirit ( or god but less likely if it is a real one ) into a (hopefully?) friendlier one.
My take is the first one because it still has spikes and stuff coming out of it, but you could argue its a matter of power...
It could also just enjoy cosplaying like all the park visitors
But the idea that she transformed the ghost/spirit / whatever is much more funny to me.