Cloud simulation tools are essential for modeling and evaluating complex cloud computing infrastructures, enabling researchers to study resource allocation strategies, scheduling algorithms, and overall system performance. CloudSim Plus is a widely used Java framework for building such simulations. However, despite its rich feature set, it offers only limited support for post-simulation analysis, providing primarily static ASCII tables that summarize final resource states. As simulation complexity grows, this output format becomes insufficient, highlighting the need for more interactive and insightful analysis tools. In this work, we present Cooper, a lightweight and modular visualization framework that extends CloudSim Plus with standardized event collection and timeline-based visualization. Cooper enables detailed temporal analysis of simulation runs, helping users understand dynamic system behavior, resource utilization patterns, and the effects of scheduling decisions. The event logging library runs entirely in memory, introduces minimal runtime overhead, and does not require external database or server infrastructure. Its design reduces integration effort and promotes reproducibility by decoupling simulation from visualization.