Vynhelon, I can see that you are a new user to the forums. As mentioned by Krusade above, players are not permitted to post accusations of in-game misconduct here in the forums. For this reason, yoiur thread is now closed and the opening post removed.
Please follow the advice offered above and report the alleged offender in-game. Your report will capture the evidence Jagex requires to act. Similarly, you can use your
list, to mute the player. By adding him/her to that list, you will not see any chat in any of the modes.
Before you post again, please make sure that the topic you wish to discuss is appropriate. Avoid posting this content (or similar) again.