Despite my mods list as follows,it still happened when I started Rimworld.
[Mod list length: 7]
Harmony
Core
Royalty
Ideology
Vanilla Expanded Framework
Mod Manager
Kyulen - NinetailFox


Failed to find RimWorld.TraitDef named Virgin. There are 44 defs of this type loaded.
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
Verse.DefDatabase`1<RimWorld.TraitDef>:GetNamed (string,bool)
System.Reflection.MonoMethod:Invoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
System.Reflection.MethodBase:Invoke (object,object[])
Verse.GenGeneric:InvokeStaticMethodOnGenericType (System.Type,System.Type,string,object[])
Verse.GenDefDatabase:GetDef (System.Type,string,bool)
RimWorld.DefOfHelper:BindDefsFor (System.Type)
RimWorld.DefOfHelper:RebindAllDefOfs (bool)
Verse.PlayDataLoader:DoPlayLoad ()
Verse.PlayDataLoader:LoadAllPlayData (bool)
Verse.Root/<>c:<Start>b__6_1 ()
Verse.LongEventHandler:RunEventFromAnotherThread (System.Action)
Verse.LongEventHandler/<>c:<UpdateCurrentAsynchronousEvent>b__27_0 ()
System.Threading.ThreadHelper:ThreadStart_Context (object)
System.Threading.ExecutionContext:RunInternal (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object)
System.Threading.ThreadHelper:ThreadStart ()