As used in this chapter, “consolidate” includes consolidation and merger and “reinsurance” includes only those obligations ceded or assumed by an assumption agreement. An “assumption agreement” is one that transfers all of the direct insurer’s obligations under policies of insurance to another insurer and relieves the transferring insurer of any obligations under the policies. A domestic insurance company organized on the stock, mutual, stipulated premium, or assessment plan may not consolidate with any other company, or reinsure its risks or any part thereof with any other company, or assume or reinsure the whole or any portion of the risks of any other company, except in the manner provided by this chapter.