/usr/include/ is in libenki-dev 1:1.6.0-5.
This file is owned by root:root, with mode 0o755.
..
/usr/include/viewer/
/usr/include/enki/
/usr/include/enki/BluetoothBase.h
/usr/include/enki/Geometry.h
/usr/include/enki/Interaction.h
/usr/include/enki/PhysicalEngine.h
/usr/include/enki/Random.h
/usr/include/enki/Types.h
/usr/include/enki/interactions/
/usr/include/enki/interactions/ActiveSoundSource.h
/usr/include/enki/interactions/Bluetooth.h
/usr/include/enki/interactions/CircularCam.h
/usr/include/enki/interactions/GroundSensor.h
/usr/include/enki/interactions/IRSensor.h
/usr/include/enki/interactions/Microphone.h
/usr/include/enki/robots/
/usr/include/enki/robots/DifferentialWheeled.h
/usr/include/enki/robots/e-puck/
/usr/include/enki/robots/e-puck/EPuck.h
/usr/include/enki/robots/khepera/
/usr/include/enki/robots/khepera/Khepera.h
/usr/include/enki/robots/marxbot/
/usr/include/enki/robots/marxbot/Marxbot.h
/usr/include/enki/robots/s-bot/
/usr/include/enki/robots/s-bot/Sbot.h
/usr/include/enki/robots/s-bot/SbotObject.h
/usr/include/enki/robots/thymio2/
/usr/include/enki/robots/thymio2/Thymio2.h
/usr/include/viewer/Viewer.h