/usr/include/libktorrent/net/ is in libktorrent-dev 1.1.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/libktorrent/net/address.h
/usr/include/libktorrent/net/bufferedsocket.h
/usr/include/libktorrent/net/downloadthread.h
/usr/include/libktorrent/net/networkthread.h
/usr/include/libktorrent/net/poll.h
/usr/include/libktorrent/net/portlist.h
/usr/include/libktorrent/net/reverseresolver.h
/usr/include/libktorrent/net/serversocket.h
/usr/include/libktorrent/net/socket.h
/usr/include/libktorrent/net/socketdevice.h
/usr/include/libktorrent/net/socketgroup.h
/usr/include/libktorrent/net/socketmonitor.h
/usr/include/libktorrent/net/socks.h
/usr/include/libktorrent/net/speed.h
/usr/include/libktorrent/net/uploadthread.h
/usr/include/libktorrent/net/wakeuppipe.h