I get some(a lot) red text on this about 2 minutes after my save loads. I'm not quite sure what it's doing.

Here's an example:

Negative weight in selector: -28165.03 from [VFEV_Njorun, -28165.03]
Verse.Log:Error(String, Boolean)
Verse.GenCollection:TryRandomElementByWeight(IEnumerable`1, Func`2, KeyValuePair`2&)
Verse.GenCollection:RandomElementByWeightWithFallback(IEnumerable`1, Func`2, KeyValuePair`2)
RimGacha.WorldComp_BiomeManager:GetRandomGlobalAnimalWeighted()
RimGacha.Comp_AnimalDesign:.ctor()
System.Reflection.MonoCMethod:InternalInvoke(Object, Object[], Exception&)
System.Reflection.MonoCMethod:InternalInvoke(Object, Object[])
System.RuntimeType:CreateInstanceMono(Boolean)
System.RuntimeType:CreateInstanceSlow(Boolean, Boolean, Boolean, StackCrawlMark&)
System.RuntimeType:CreateInstanceDefaultCtor(Boolean, Boolean, Boolean, StackCrawlMark&)
System.Activator:CreateInstance(Type, Boolean)
System.Activator:CreateInstance(Type)
Verse.ThingWithComps:Verse.ThingWithComps.InitializeComps_Patch1(ThingWithComps)
Verse.ThingWithComps:PostMake()
Verse.ThingMaker:Verse.ThingMaker.MakeThing_Patch2(ThingDef, ThingDef)
ItemRequests.CostCalculator:GetBaseThingCost(ThingDef, ThingDef)
ItemRequests.ThingDatabase:CreateThingEntry(ThingDef, ThingDef, Gender, ThingType)
ItemRequests.ThingDatabase:CreateThingEntry(ThingDef, ThingDef, ThingType)
ItemRequests.ThingDatabase:AddThingDef(ThingDef, ThingType)
ItemRequests.ThingDatabase:AddThingToThingLists(ThingDef)
ItemRequests.ThingDatabase:ProcessThings()
ItemRequests.ThingDatabase:LoadFrame()
ItemRequests.DatabaseAsyncLoaderLoadedGame:LoadDBFrame()
Verse.Game:Verse.Game.UpdatePlay_Patch3(Game)
Verse.Root_Play:Verse.Root_Play.Update_Patch1(Root_Play)