Mix vinegar, sugar, and salt in a 3:3:1 ratio in a small bowl to create sushi vinegar. Add it to the cooked rice and mix well.

Wash the cucumbers thoroughly and slice them thinly into 10-15 strips using a vegetable peeler.

Julienne the remaining cucumber and place it in a mixing bowl.

Shred the crab sticks and thinly slice the onion, then add them to the mixing bowl.

Add 1 tbsp of mayonnaise, 1 tsp of sugar, and a pinch of salt to the mixing bowl. Mix well to create the crab stick sauce.

Mix the cooked rice with the prepared sushi vinegar and a small amount of sesame oil.

Shape the seasoned rice into bite-sized portions and wrap each with a cucumber slice.