The Stylo 7 is currently rumored to become the latest in a line of LG phones with an in-built digital pen. Its latest leak shows that it has a rear panel that makes this abundantly clear. It is designed to look as though it has been moulded around the housing for this stylus, with an additional separate hump for its rear cameras.
https://www.notebookcheck.net/Leaked-renders-show-the-LG-Stylo-7-s-rear-panel-is-designed-to-accentuate-its-pen-silo.505577.0.html