What 
Girl Next Door says when short on supplies. Every mood's lines are on their page.
60% of the time, then a cooldown of 1 hour.
Details1
Says one of these
1- "I don't seem to have enough supplies. I need to use them sparingly..."
From the game files1
NpcMonologue 4
| ID | 4 |
|---|---|
| NpcConfigId | 2 |
| MoodType | 3 |
| Rate | 0.6 |
| TypeCD | 3600 |
| RandomText | ["NpcMono_Girl_LowMat_1"] |