Despite the naps taken when he's on the road, as a deep sleeper, Elio's quite comfortable... for the most part.

While he's trained himself to slumber in practically any environment, per his survival training, Elio normally rests in a king-sized therapeutic bed - both as a sign of his affluence and to accommodate his ever-growing stature. Typically, it's layered with patterned sheets (and at times, a comforter) to give the silver-haired trainer some level of warmth in his sleep; however, there are times when he'll sleep uncovered - mainly when the weather's hot.

Ever since he started his education at TUA and quickly advanced in his Aura and Martial Arts training - resulting in a notable stimulation of his physicality, Elio's started to sleep half-naked: wearing only his underwear and socks due to an uneven distribution of body heat via its constantly-active state. Though this issue would die down around the later aspects of his second year, Elio's propensity for sleeping half-nude would become ingrained.

On a side note, certain smaller members of his party would sneak into his bed as a sign of affection; while it's pretty common with Estio, Emaure, Eldrick, and Molesurya (in lieu of its large size), and formerly done by Jupiter, Lucifel, Rowen, and Heim prior to their respective evolutions, some of his other friend's Pokemon would get into that habit because of how much Elio takes care of them (i.e. Andrew's Yamper, Taejin's Vulpuix (pre-evolution), Ashe's Mimikyu, etc.).