Somehow, I got the corruption on the sys.ifts_comp_fragment_xxxx_yyyy while running DBCC checkDB.
While the table does not actual exist but the sys.ifts_comp_fragment_xxxx_yyyy is translate from the actual system table - Sys.fulltext_index_fragments
The system table Sys.fulltext_index_fragments contains the fragmentation information for full text index.
XXXX is the object id of the table where has the full text index. YYYY is the fragment id.
According to the MSDN blog here, the author suggest to drop/recreate the full text catalog to resolve the issue.
My case has a slightly difference situation. The base table where the full text index exist has actually page corruption. So I have to fix the corruption first ( DBCC CHECKDB REPAIR_REBUIL … etc).