It's supposed to be based off of the characters' powers. Papyrus makes your soul indigo, which is similar to the soul of Integrity. Undyne makes your soul green, which is simialr to the soul of Kindness, and so on, so forth.
The hearts represent a few of the six souls, each color has a different meaning, your soul changes colors in each of these fights, possibly to represent each character
Muffet was doing her best to save the spiders, with all the bakesales and fundraisers... I feel so bad for her. If you kill her without having bought anything from her, she drops 0g. She was never greedy, she was literally just super poor. Its freakin sad.......... ANYWAY what's up with yall
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0 ups, 2y
i . . u n d e r s t a n d . . t h a t . . u n d y n e . . i s . . k i n d n e s s
no, these are the colors the soul changes to in each fight, and they match some of the soul colors that have meanings, so i was seeing how well they connect to each character
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0 ups, 2y
Yes but still, undyne being kindness doesn’t make any sense.