Cloth

A cicada who set out to Hallownest in order to become a true warrior, and sees The Knight as an inspiration. However, her cowardly nature often leads to her hiding underground in various areas, where the player can talk to her after clearing the place of enemies. To trigger Cloth's appearance in the Traitor Lord fight, she must be saved in the Ancient Basin location prior to the fight. The player may talk to Cloth at all other locations with no effect on the quest ending. If Cloth is present in the Queen's Gardens location, then she will appear during the Traitor Lord fight. She will always die during this fight.

Cloth mentions a character by the name of "Nola" who ties into both endings to her quest. It is unclear who this is, but it is indicated that they are dead. Evidence that points to this are that Cloth only states that she can join Nola after dying to Traitor Lord. If she wasn't killed and ends up in Dirtmouth, her Dream Nail dialogue implies that she will keep trying to seek out harder foes until one finally ends her life- to join Nola in death.

First Encounter, Fungal Wastes
Cloth can be first encountered in Fungal Wastes north of the entrance to the City of Tears. She tells the Knight of the Mantis Tribe that can be found further south.

Second Encounter, Deepnest
If she has not yet been encountered in Ancient Basin, Cloth can be found on the Bench in the Failed Tramway in Deepnest. She talks about leaving Deepnest since she finds it too challenging for her.

Third Encounter, Ancient Basin
West of the tram in Ancient Basin, Cloth can be found at the very end of the area where she needs to be rescued. She will be located even if she has not been encountered in other locations. After the Aspid Hunters and Lesser Mawleks have been defeated, Cloth will come out of hiding. She tells the Knight that she takes strength from their example of courage, and that she will attempt to match it the next time they meet.

Fourth Encounter, Queen's Gardens
If she is rescued in Ancient Basin, Cloth can be encountered at the Fog Canyon entrance to Queen's Gardens. She talks about being willing to test herself against the Mantis Traitors who inhabit the Gardens.

Final Encounter, Traitor Lord or Dirtmouth
After Cloth is rescued in Ancient Basin, she will help the Knight in the fight against Traitor Lord. At the end of this fight, she will deal the final blow to him, but will also die herself. Once the Knight leaves the area and returns, Cloth's ghost can be found above her corpse, mentioning that she will be on her way soon. After leaving the area again, her ghost will have disappeared.

If she is not rescued first in Ancient Basin before fighting Traitor Lord, Cloth will move to sleeping outside of Sly's shop in Dirtmouth. She says that she will leave Hallownest soon since she did not find the right challenge there. She will be asleep here until the Knight leaves the area and returns, after which she will be gone.

Locations
Cloth can be found in several locations across Hallownest. If she is encountered in Queen's Gardens, she cannot be found in Dirtmouth and vice versa.

Trivia

 * Cloth was the first Backer NPC announced. Backer NPCs were a reward tier on the Hollow Knight Kickstarter page:
 * "Cloth is a Cicada-type warrior to meet on your quest through the caverns. Just listen for his Cicada song and you’ll know he’s close. Cloth’s a friendly sort, though he’s having doubts about his combat prowess. As the Hollow Knight, you can help Cloth regain his morale and in doing so gain his assistance through some tough battles. Watch out though! Cloth isn’t invincible and without the two of you working together he may end up meeting a warrior’s demise."
 * "Fun Fact: Cloth was originally called Burlap until we realised burlap, the material, doesn't exist in Hallownest so he underwent a name change. We’re still working with Noah to finalise Cloth so look forward to his exciting (possibly tragic) tale when you play the final game."
 * Despite the pitch, Cloth only aids the Knight during the battle with the Traitor Lord. If she is present during that battle it will always end with the Lord impaling Cloth and the Cloth delivering the final blow to the Lord's skull, killing them both.
 * Although pitched as male during the Kickstarter campaign, the official manual and developer notes denote Cloth as female.
 * There is always rumbling before Cloth pops out of the ground in any area; this is accompanied by the same sound effects as when the player walks on a breakable floor.
 * Her club can be seen resting on the grave of the Traitors' Child in the background of the Traitor Lord fight in Godhome, if she is killed in battle.