CTD encountered in version Minestuck-1.12.2-1.4.287 in conjunction with LittleMaidReengaged-8.1.6.141-peko_build-1.1.1.
I am unsure if it is a problem in Minestuck or LittleMaid, but it appears to be crashing on attempting to add Grist to the Maid Entity's Grist Cache.
Will attempt to replicate with other gathering-follower-type mods and attach them as found

Description: Ticking entity
java.lang.NullPointerException: Ticking entity
at com.mraof.minestuck.alchemy.GristHelper.getGrist(GristHelper.java:120)
at com.mraof.minestuck.alchemy.GristHelper.increase(GristHelper.java:188)
at com.mraof.minestuck.entity.item.EntityGrist.consumeGrist(EntityGrist.java:243)
at com.mraof.minestuck.entity.item.EntityGrist.func_70100_b_(EntityGrist.java:231)
at net.blacklab.lmr.entity.littlemaid.EntityLittleMaid.func_70636_d(EntityLittleMaid.java:2183)
at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:2172)
at net.minecraft.entity.EntityLiving.func_70071_h_(EntityLiving.java:295)
at net.blacklab.lmr.entity.littlemaid.EntityLittleMaid.func_70071_h_(EntityLittleMaid.java:2414)
at net.minecraft.world.World.func_72866_a(World.java:1993)
at net.minecraft.world.WorldServer.func_72866_a(WorldServer.java:832)
at net.minecraft.world.World.func_72870_g(World.java:1955)
at net.minecraft.world.World.func_72939_s(World.java:1759)
at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:613)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:767)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:185)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
at java.lang.Thread.run(Thread.java:745)

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head
--Thread: Server thread
Stacktrace:
at com.mraof.minestuck.alchemy.GristHelper.getGrist(GristHelper.java:120)
at com.mraof.minestuck.alchemy.GristHelper.increase(GristHelper.java:188)
at com.mraof.minestuck.entity.item.EntityGrist.consumeGrist(EntityGrist.java:243)
at com.mraof.minestuck.entity.item.EntityGrist.func_70100_b_(EntityGrist.java:231)
at net.blacklab.lmr.entity.littlemaid.EntityLittleMaid.func_70636_d(EntityLittleMaid.java:2183)
at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:2172)
at net.minecraft.entity.EntityLiving.func_70071_h_(EntityLiving.java:295)
at net.blacklab.lmr.entity.littlemaid.EntityLittleMaid.func_70071_h_(EntityLittleMaid.java:2414)
at net.minecraft.world.World.func_72866_a(World.java:1993)
at net.minecraft.world.WorldServer.func_72866_a(WorldServer.java:832)
at net.minecraft.world.World.func_72870_g(World.java:1955)
-- Entity being ticked
--Details:
Entity Type: lmreengaged:littlemaid (net.blacklab.lmr.entity.littlemaid.EntityLittleMaid)
Entity ID: 6587
Entity Name: entity.LittleMaid.name
Entity's Exact location: -51.60, 72.00, 158.25
Entity's Block location: World: (-52,72,158), Chunk: (at 12,4,14 in -4,9; contains blocks -64,0,144 to -49,255,159), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Entity's Momentum: 0.00, -0.08, 0.00
Entity's Passengers: []
Entity's Vehicle: ERROR NullPointerException: null
Stacktrace:
at net.minecraft.world.World.func_72939_s(World.java:1759)
at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:613)
-- Affected level
--Details:
Level name: New World
All players: 1 total; [EntityPlayerMP['JediaKyrol'/2275, l='New World', x=-53.44, y=73.00, z=162.61]]
Chunk stats: ServerChunkCache: 1089 Drop: 0
Level seed: -1044054573090020207
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (0,0,0), Chunk: (at 0,0,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 0 game time, 0 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: ERROR NullPointerException: null
Stacktrace:
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:767)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:185)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526)
at java.lang.Thread.run(Thread.java:745)