In his 6th house. Here the original question: my S.N. (which is in Saggitarius, in my 6th house) is conjunct his NN (in Sagittarius, in his 6th house). Alternatively, his South node (Gemini, 1st house) is conjunct my North Node (in Gemini, 1st house). His S.N. is conjunct my Chiron (in my 1st house) and that my S.N. is conjunct his Neptune, (in his 6th house).
http://www.astroknowlogy.com/questions/what-is-the-meaning-of-north-node-in-virgo-in-the-4th-house-in-a-composite-chart
Answer
chiron in signs and houses
learn about composite charts
“Neptune Conjunct North Node: You’re attuned to what is socially popular and acceptable. You’re intuitively at the right place at the right time. However, you tend to get swept along in fads and often go along with the crowd because it’s the easy way out and this can lead to disaster. You must learn to exercise discrimination.” http://www.oocities.org/rbltre/astro/neasnn.html
now although Neptune can be spiritual it ALSO can be illusions, confusions and delusions around matters of SOuth Node house
So South Node is past habits and comfort zone, and North Node is the area where New patterns of behaviour and habits can be formed.
“Chiron in Aspect to the Moon’s Nodes -this is for Natal so just Adapt…. This is confined to comments about the square and conjunction. When Chiron squares the Nodes, individuals may feel blocked by their wounds, and limitations; they stumble over the same issues (suggested by house and sign placement) every time they try to go forward in life. They often have a strong sense of destiny which will not let them rest ! With Chiron squaring the Nodes, out limitations and wounds need to be included in our self concept and idea of our purpose in life; any attempts to forge ahead by trying to exclude them result in crisis. Our whole idea of self actualisation may need to be re examined, perhaps transformed from an ¬achievement oriented and one sided idea of "spiritual progress” to one which addresses the whole person. The lives of people who have Chiron conjunct either Node strongly reflect the Chironian themes. They may embody one of the figures from the myth, living out the role of teacher, wise person, healer, mentor, saviour, victim, sufferer, wounded one, wounder, devotee or apprentice. They will have a strong sense of VOCATION in Chironian fields such as teaching or healing; alternatively they may have intimate relationships with therapists, priests, people who are ill or physically or mentally handicapped.
When Chiron is in hard aspect to the Nodes, if its themes are not lived consciously, perhaps through commitment to a personal quest for consciousness or following a healing vocation; they usually manifest themselves anyway, and can even take over the person’s life in a negative way."
natal chiron in first house is the mark of a healer, great at helping others but not great at taking your own advices.