Sheela-na-gigs, which appear on churches and castles across Ireland and Britain from roughly the twelfth century onwards, are still imperfectly understood, but finding one so directly integrated into a window's structure, effectively forming its crowning stone, is genuinely unusual. The figure has a roughly triangular body, splayed legs set at uneven heights, round staring eyes, a flat nose, and ears described as sitting like cup handles on either side of the head. What makes this particular stone still more layered is that by 2007 a devotional custom had grown up around the same window, with pilgrims scratching crosses into the side stones and the sill using a rough stone left on the ledge for the purpose. The sill stone, worn and cracked through repeated use, bears witness to two very different kinds of attention.

The church sits on an elevated, south-to-north sloping site in the parish of Dysert, Diocese of Ardfert, in the barony of Trughanacmy, Co. Kerry. By 1987, when the Castleisland District Archaeological Survey examined the site, only the eastern gable and the eastern portion of the south wall were still standing, the rest long since collapsed or absorbed into the graveyard that had grown up inside and around the ruin. The east gable contains a second window, originally divided into two ogee-headed lights by a central mullion that is now missing; a hood-moulding survives above it. Both surviving windows are built in cut limestone, while the broader wall fabric mixes large sandstone blocks with flatter stones. A broken piscina, a small stone basin once used for draining water from the chalice after Mass, survives in the southeast corner of the interior. By 2007, when surveyor Laurence Dunne examined the site, the east gable window was so heavily engulfed in ivy that the stonework could not be properly assessed, and its sill had become a makeshift altar holding holy statues and rosary beads.

The pilgrim tradition at Kilsarkan is old and specific. A 1942 account describes people coming on Fridays, Saturdays, and Sundays throughout May to walk around the graveyard three times, reciting a Rosary on each circuit. At the close of the third Rosary, the pilgrim was to touch the carved figure above the south window, which local folklore identified not as a sheela-na-gig but as an image of St Arcan, patron of the parish. Prayers were then said before the holy pictures kept in a cavity in the wall, and something, usually a religious pamphlet or booklet, was left at the foot of the old masonry before departing. The rounds were said for cures or for the souls of the dead. That a figure now classified by archaeologists as a sheela-na-gig should be remembered locally as a saint's image, and should continue to attract devotional practice into the present century, says something quietly remarkable about the long afterlife of medieval stonework in the Irish landscape.