If your replication is set in master ---> slave mode, there is no problem in writing to a slave table, even if the table is present in master. It wont affect the replication process. In your case, the only possible cause for a replication failure would be when you create a table in your master, which is already in the slave.
So the answer for your question is your replication won't break if you do this.
Here is a good refernce