The short answer for five-lined skinks
A five-lined skink can sometimes live with another of its own kind, but solitary housing is the low-risk default and two adult males together is a pairing to rule out completely. Males are territorial around basking spots and shelters, and a confrontation in a small glass box has nowhere to end except in bites, chased animals, and dropped tails. Females are usually calmer company for each other, and juveniles raised together often coexist for a while, yet tolerance is not the same as companionship. These skinks do not seek each other out for comfort. At best, a compatible pair simply manages to avoid friction inside a shared space.
Why skink temperament decides the pairing
Five-lined skinks spend their days slipping between leaf litter, bark, and warm edges, and an adult male treats the best of those places as his to defend. Put two males in sight of each other and the brighter, bolder animal usually starts displaying, then chasing, then biting at legs and flanks. The loser cannot leave the territory the way he would outdoors, so stress continues long after the first scuffle. Females lack that same drive to expel a rival, which is why female pairs are the only adult combination keepers discuss seriously. Even then, one female may quietly claim the warm hide and the food bowl, leaving the other thinner, cooler, and hiding more each week.
Setting up a shared skink enclosure that gives both animals an exit
If you attempt a female pair, size and clutter matter more than good intentions. Choose a long enclosure rather than a tall one, since these skinks live on the ground, and build the floor into separate neighbourhoods: a hide at the warm end and another at the cool end for each animal, pieces of bark that break sightlines, and leaf litter deep enough to disappear into. Offer food in two separated spots so the subordinate skink can eat without crossing the dominant one's path. Basking access needs duplicating as well, because a skink pushed off the warm spot day after day cannot digest properly or shed cleanly.
Signs a skink pairing is failing
Watch behaviour, not wounds alone, because trouble starts earlier than blood. One skink always in the prime basking place while the other stays buried is a warning, as is rapid weight loss in the shyer animal, uneaten food despite a good appetite when fed alone, and frantic glass-surfing after lights come on. A dropped tail, bite marks along the sides, or one animal going suddenly still and flat when the other approaches all mean the experiment is over. Separate first and assess afterwards; a skink that has been bullied for weeks often feeds eagerly within days of getting its own enclosure, which tells you how much the sharing was costing it.
The safer way most keepers house five-lined skinks
Solo housing removes every one of these negotiations, and it suits an animal that hunts, basks, and shelters alone by nature. A single skink still needs the same long floor plan, layered cover, and warm-to-cool gradient, but every resource in it is uncontested. If you keep several skinks, stacked or side-by-side individual enclosures let you enjoy a small collection while feeding, shedding, and health can be tracked animal by animal instead of guessed from a shared bowl. That individual record matters when one animal goes off food: in a shared tank you may not even know which skink ate yesterday.
Keeping two skinks' details straight
Whether your skinks end up paired or apart, write down which animal basks where, who shed when, and which one refuses food during cooler weeks, because two blue-tailed youngsters can look nearly identical at a glance. Share those notes with anyone who feeds them while you are away, since a helper who cannot tell the skinks apart cannot spot the shyer one missing meals. KinsLe Family Sharing keeps each five-lined skink's profile and care information available to the family members who help, so both animals are looked after from the same details rather than from memory.