Caller
... Kris...
... don't forget, Kris...
... you promised.Caller, Chapter 4
The caller is an unidentified character or set of characters who contact Kris via phone calls in Chapter 4 of Deltarune.
The caller(s) have knowledge that is not typically known in the Light World. This includes the existence of Dark Worlds, knowing where the next Dark Fountain will appear, that Kris needs the SOUL, and that Dess's guitar contains a code.
The calls from Kris's Cell Phone have the caller's dialogue presented as a spiked speech bubble, which has a sharp, echoing sound that plays at the start of each line of dialogue.
Many of the caller's words are omitted by ellipses, which heavily fragment their sentences and render them incomplete. Their dialogue can also appear in red text, which occurs when they are talking about Susie.
In the Japanese translation of Deltarune, the caller similarly speaks in incomplete sentences and occasionally truncates words, such as "わすれな" (wasurena) instead of "わすれない" (wasurenai — "don't forget"). This might be intentionally done to further obfuscate the caller's identity by avoiding gender- or age-specific manners of speech.
Kris takes part in three phone calls while the SOUL is removed from their body. All calls are on speaker and uses a unique sound.

The first call occurs during Kris and Susie's investigation at Noelle's House. The player, controlling the SOUL, enters the kitchen's air vents, where Kris is on the phone with the caller. The dialogue in these calls is fragmented, alternates between white and red text colors, and ends with ellipses.
In white text, the topics of discussion include Dark Fountains,[1] a plan for the church that night,[2] the SOUL,[3][4] and something regarding the police and a sacrifice the following week.[5] The red text is segmented instructions, emphasizing Susie should not get the guitar, which has a code for the shelter.[6][7] When Susie does obtain the guitar, Kris makes a phone call, and receives the white text "I'll be... right there..." Shortly after, Carol returns home early.

After returning to the Dreemurr residence, Kris receives a phone call while they are atop the windowsill. This caller in white text urges Kris not to forget the promise they made.
On the Weird Route, Kris instead receives a call while in bed, and they place the phone to their ear. This dialogue is presented as normal, is narrated with Carol's sound bite, and excludes her dialogue portrait in the dialogue box. The caller asks if Kris is there, and then leaves a message. It is to confirm Kris's attendance at the festival, and ends with stating Noelle is "really looking forward" to seeing Kris.
- ↑
... dark... fountain... next...
— Caller, Chapter 4 - ↑
... church... tonight...
— Caller, Chapter 4 - ↑
... need... soul...
— Caller, Chapter 4
Without... soul... Kris... will... - ↑
... Kris... dark world... no soul... can't...
— Caller, Chapter 4 - ↑
... police... sacrifice... next week...
— Caller, Chapter 4 - ↑
... Susie... must not get... guitar...
— Caller, Chapter 4 - ↑
... Susie... guitar... code... stop...
— Caller, Chapter 4 - ↑
タマシイ…ない… クリス…やみのせかい… はいれな…
— Caller, Chapter 4 Japanese localization - ↑
While in English, "can/cannot" is its own verb, Japanese typically expresses this by instead modifying the original verb itself, so we actually now know what "can't" in the English version was referring to--the full phrase was "can't enter."
— duxarcana on Tumblr, July 01, 2025.