Sabiu ‘Tunde’ Yusuf, the personal secretary to President Muhammadu Buhari who is in his 30s, is set to retire with the biggest retirement benefit from loot said to run into billions of dollars. And to ensure he enjoys his loot, SaharaReporters learnt that Yusuf secured a form of diplomatic immunity from prosecution through his appointment to the National Intelligence Agency, according to sources in the Presidency.