This paper presents our aspect-oriented system specialized for debugging named Bugdel. Bugdel is a plug-in module for Eclipse, which is an integrated development environment. Unlike other general-purpose aspect-oriented systems, Bugdel allows user to specify aspects using a graphical user interface. Furthermore, Bugdel provides new functions that AspectJ or others do not provide, since they break the modularity of classes. This paper discusses limitations of related general-purpose aspect-oriented systems, such as AspectJ, and shows the solutions that we have implemented in Bugdel.