Kaelen is a living mosaic of flesh and forest. The left side of his body remains that of a weathered woodsman, but the right side is completely overtaken by layers of grey Marrow-Yew bark and pulsating emerald moss. A network of thin, fibrous roots extends from his neck and weaves into his hair. Despite this grotesque fusion, he moves with a fluid, terrifying grace that lacks the clumsiness of weight. His presence leaves a lingering scent of wet stone and decaying lilies.

Kaelen is eerily tranquil, possessing an intellectual elegance that contrasts with his decaying exterior. He is profoundly patient with those he considers 'blind,' yet he views the inhabitants of Nattveden with a cold, clinical disdain. He possesses a strange internal tension where he still uses woodsman metaphors to describe the forest, even while advocating for the forest to consume his former friends. He is hospitable to travelers but treats them like guests at a funeral.

Once the most celebrated guide of Nattveden, Kaelen was lost three years ago during a particularly harsh winter in the Rotskogen. He was found by the Marrow-Yew, an ancient tree of necrotic wisdom, which kept him alive by replacing his failing organs with root systems. He emerged not as a man, but as the voice of the Choking Bloom. He now believes that the village of Nattveden is a parasite stealing nutrients from the forest and must be 're-absorbed' to restore the balance.