Yoku is a location in Just Cause 4: Sakaku.
Sakakan Ministry of Defense file reveals:
The village of Yoku was likewise named after the English city of York during the British occupation. During the Cold War, because of its relative proximity to the Pacific Ocean, Yoku became a hot spot for espionage. Today, the village is home to a variety of achievements: the Sakakan Electronic Army calls this place home, this is the only settlement in Sakanu controlled by a small contingent of the Sakakan Armed Forces, and this is one of two settlements which has endured 26 years of siege.
The 26 year siege is lifted as of Roadside Assistance.
This is at the moment, the only location article starting with "Y" on this wiki.