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  1. Life Cycles by

    Fandoms: Undertale (Video Game)  

    31 Aug 2025

    Tags
    Summary

    The Fell monsters have never gone into heat before, have never heard of it. Now that they've reached the surface, though, it's only a matter of time before biology reasserts itself.

    Few of them are taking the news all that well.

    Language:
    English
    Words:
    164,260
    Chapters:
    40/?
    Collections:
    2
    Comments:
    652
    Kudos:
    554
    Bookmarks:
    70
    Hits:
    18,694