Explained: The proceedings Spanish football chief Luis Rubiales could face
Hermoso says she did not want to be kissed, and that she felt "vulnerable and a victim of an aggression".
Rubiales, who refused to resign on Friday despite heavy pressure, said the kiss was "spontaneous, mutual, euphoric and consensual".
He and his federation have said they will take their own legal action to defend him and prove his innocence on all accusations.
WILL THERE BE SPANISH CRIMINAL PROCEEDINGS?
The prosecutor at the Spanish High Court, which has jurisdiction as the soccer final was abroad, has received several complaints alleging possible sexual aggression.
In such cases, and when the victim is adult and capable, prosecutors cannot act on their own. The High Court prosecutor said on Monday the office would contact Hermoso to ask her if she wants to formalise a criminal complaint.
In the meantime, the prosecutor has started a pre-proceedings investigation, which would stop if Hermoso does not file a complaint within 15 days from being contacted.
Sexual aggression carries a prison term of between one and four years in prison.
At the final, Rubiales was also seen grabbing his crotch in celebration while standing next to Queen Letizia and 16-year-old Princess Sofia. He has apologised for the gesture.
One of the complaints received by the prosecutor also covers that episode, accusing Rubiales of "obscene exhibitionism in the presence of a minor".
WHAT IS FIFA DOING?
World soccer governing body FIFA suspended Rubiales from all football-related activities for three months with immediate effect on Saturday.
Its Disciplinary Committee opened proceedings based on article 13 in its code, which deals with "offensive behaviour" of players and officials, particularly with "violating the basic rules of decent conduct" and "behaving in a way that brings the sport into disrepute".
Rubiales said he would use the probe to show his innocence.
WHAT ELSE ARE THE SPANISH AUTHORITIES DOING?
The Spanish government has strongly condemned Rubiales' actions but can not directly suspend or remove Rubiales from his post as president of the Spanish Royal Football Federation (RFEF), which is a private institution.
Instead, the state-run National Sports Council (CSD) on Friday sent the Rubiales file, consisting of complaints by several organisations including Spain's women's football league, to its Sport Administrative Court (TAD) alleging two "very serious breaches": abuse of authority and "public acts that violate sporting dignity or decorum".
CSD said the complaints covered "all his behaviour during the final".
The TAD is holding an extraordinary meeting on Monday and is due to decide whether to take up a case against Rubiales. The court has seven members, including three women, who are appointed by the CSD.
Only if the TAD decides to initiate proceedings against Rubiales could the CSD suspend him for the duration of the investigation, a decision that has to be adopted by the CSD executive committee.
The committee can meet 48 hours after the TAD decision, at the earliest. Although Rubiales is already suspended, Spain's CSD said it would move ahead with its own case regardless.
Spain's sports law states that if someone is found to have engaged in "very serious misconduct" they could be removed. He could also be disqualified from holding office in a sporting body for a period of between two and five years.
The ruling could take several months, including analysing all the documentation and allegations from the parties.
The law envisages disqualification for life from holding office in a sports organisation in case of repeat offences and depending on how serious they are.
