An obvious couloir, very steep and very alpine, a pretty way to reach the highest peak of Dévoluy.

Petit Obiou : SE couloir

From the parking, follow the Sapey forest road which leads to the Faïsses pass. Leave it around 1330m or 1480m to climb the steep slopes of "Ravin du Cros des Casses".
Around 1850m, get over the rock barriers by a narrow couloir to reach the upper slopes (named "Pré Chevalier" on IGN map). Continue straight in the couloir or, around 2100m, cross on left to reach anothe parallel couloir (equally steep). Carry straight on up to the foot of beautiful yellow rock towers, and enter in a very steep and narrow couloir (in Summer it is a rock chimney). Climb it to reach an horizontal snow ridge near the Petit Obiou, and get easily to the Petit Obiou pass.

Obiou head

From Petit Obiou, there are two possibilities:

by the "Chatières" route:
from the pass, take the NW slopes under the head of Obiou (45° sections) and cross the middle rock barrier by a short climb (diagonal ramp). Continue up to the foot of the "Chatières" opening (cave tunnel in the rock) around 2710m. Leave the skis here and climb the tunnel on about 80m up to the summit (easy in Summer, but more problematic in Winter). by the "Cravatte" route:
follow the wide snow ridge in S direction up to the foot of a rock bastion (slab rock stairs with summer path markups). Climb it up to a horizontal snow line. Then cross on left and pass under a big overhanging rock to arrive above a couloir with a jammed block. Follow up the the corridor (snow slope) which leads directly to the summit.

Descent

Ski down the ascent route.

Variants:

by the normal route:
join the Petit Obiou pass by the ascent route. Then ski down the N slope of the "Combe du Petit Obiou". by Malpasset peak:
from the summit, go down SW along the ridge to reach a small pass. Then continue up to the Malpasset snowy dome (50m ascent).puis remonter une cinquantaine de mètres jusqu'au dôme neigeux du Malpasset. From there you can either:
continue SW the ridge towards "Bonnet de l'Evêque" by crossing the Mapasset passage en franchissant le passage du Malpasset (20m very tricky) ski down the S couloir from Malpasset summit.

In both cases, reach the Fuvelle valley.

The closest ski resort is Superdevoluy / La Joue du Loup , 11 km away.