obligation – a formal, binding agreement (bond) or acknowledgment of a liability to pay a certain amount, or to perform, or forbear from performing, a certain duty for a particular person(s), whether the duty is imposed by law, contract, promise, oath, duty, or moral responsibility.

• obligee – the person to whom the duty of an obligation is owed, to whom a bond is made payable, and who is entitled to enforce a guaranty; a promisee, creditor, or donor beneficiary.
  
• obligor – a person who has undertaken an obligation; a promisor or debtor.

indemnity – a duty to make good any loss, damage, or liability incurred by another, or the right of an injured party to claim reimbursement for its loss, damage, or liability from a person who has such a duty.

• indemnify – to compensate or reimburse a person for a past or future loss or damage caused by one’s own or a third party’s act or default.
• indemnitee – someone who receives indemnity from another.
• indemnitor – a person whom indemnifies another. — aka indemnifier.