Synonyms of undemanded

2 Syllables
willing, unsought
3 Syllables
unasked, spontaneous, impudent, unbidden, presumptuous, arrogant, unprompted, unwanted, gratuitous
4 Syllables
unwelcome, uncalled-for, overbearing, uninvited, undesired, unrequested
5 Syllables
voluntarily
7 Syllables
supererogatory