/usr/lib/x86_64-linux-gnu/librelion-1.3.so is in librelion+mpi-dev 1.3+dfsg-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/librelion-1.3.so.1.0.3
/usr/lib/x86_64-linux-gnu/librelion-1.3.so.1.0.3