Leather Boots are a generic pair of leather boots for both male and female custom characters in Create-A-Soul for Soulcalibur III and Character Creation in Soulcalibur IV.
Soulcalibur III[]
These boots are a part of the female Thief class/costume.
Soulcalibur IV[]
Leather Boots raise Boost by 25, Attack by 15, and HP by 10. They are unlocked at the start of the game.